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Triangles: NCERT Class 9 CBSE
Exercise 7.1
Q1.In quadrilateral ACBD, AC = AD, and AB bisect ∠A (see the given figure). Show that
ΔABC≅ΔABD. What can you say about BC and BD?
Ans.
GIVEN:In quadrilateral ACBD, AC = AD
AB is the bisector of ∠A
So, ∠BAC = ∠DAB
TO PROVE: ΔABC≅ΔABD
PROOF: In ΔABC and ΔABD
We have
AC = AD (given)
AB = AB (common)
∠BAC = ∠DAB (given)
ΔABC≅ΔABD (SAS rule)
BC = BD (by CPCT)
Q2. ABCD is a quadrilateral in which AD = BC and ∠DAB = ∠CBA (see the given
figure ).Prove that
(i) ΔABD ≅ΔBAC
(ii) BD = AC
(iii) ∠ABD = ∠BAC
Ans.
(i) GIVEN: ABCD is a quadrilateral
AD = BC and ∠DAB = ∠CBA
TO PROVE: ΔABD ≅ΔBAC
PROOF: In ΔABD and ΔBAC
AD = BC (given)
AB = AB (common)
∠DAB = ∠CBA
ΔABD ≅ΔBAC (SAS)
Hence proved
(ii) BD = AC (By CPCT)
(iii) ∠ABD = ∠BAC(By CPCT)
Q3. AD and BC are equal perpendiculars to a line segment AB (see the given figure).Show
that CD bisects AB.
Ans.
GIVEN: AD = BC
AB ⊥ BC and AB ⊥ BC
∴∠OBC = ∠OAD = 90°
TO PROVE: CD bisects AB i.e AO = BO
PROOF: In ΔAOD and ΔBOD
Since BOA and COD is a line
∠DOA = ∠BOC (vertically opposite angle)
AD = BC (Given)
∠OBC = ∠OAD = 90°
(given)
ΔBOC ≅ ΔAOD(AAS)
AO = BO (By CPCT)
Hence Proved
Q4. l and m are two parallel lines intersected by another pair of parallel lines p and q(see the
given figure). Show that ΔABC ≅ CDA.
Ans.
GIVEN: p ∥ q and l∥ m
TO PROVE: ΔABC ≅ ΔCDA
PROOF:In the figure
l∥ m and AC is the transversal(given)
So, ∠DAC = ∠ACB (alternate angles)
p ∥ q and AC is the transversal(given)
∠BAC = ∠ACD(alternate angles)
AC = AC(given)
ΔABC ≅ Δ CDA(ASA rule)
Hence proved
Q5.Line l is the bisector of an angle ∠A and B is any point on l ,BP and BQ are
perpendiculars from B to the arms of ∠A(see the given figure). Show that
(i) ΔAPB ≅ΔAQB
(ii) BP = BQ or B is equidistant from the arms of ∠A
Ans.
(i) GIVEN: ,BP and BQ are perpendiculars from B to the arms of ∠A
∴∠AQB = ∠APB = 90°
Line l is the bisector of an angle ∠A and
∴∠QAB = ∠PAB
TO PROVE: ΔAPB ≅ΔAQB
PROOF:∠AQB = ∠APB = 90°
(given)
AB = AB (common)
∠QAB = ∠PAB (given)
ΔAPB ≅ΔAQB (AAS rule)
(ii) BP = BQ(by CPCT)
Hence proved
Q6. In the given figure, AC = AE, AB = AD and ∠BAD = ∠EAC. Show that BC =DE.
Ans.
GIVEN: AC = AE
AB = AD
∠BAD = ∠EAC
TO PROVE: BC =DE
PROOF: We have to prove BC =DE, which are sides of the triangle ΔABC and ΔADE
In triangles ΔABC and ΔADE
AB = AD(given)
AC = AE(given)
∠BAD = ∠EAC (given)
Adding both sides ∠DAC
∠BAD + ∠DAC = ∠EAC + ∠DAC
∠BAC = ∠DAE(proved)
ΔABC ≅ ΔADE (SAS rule)
BC = DE (by CPCT )
Hence proved
Q7. AB is a line segment and p is its midpoint. D and E are points on the same sides of AB
such that ∠BAD = ∠ABE and ∠EPA=∠DPB(see the given figure). Show that
(i) ΔDAP≅ ΔEBP
(ii) AD = BE
Ans.(i)
GIVEN: ∠DAP = ∠EBP
∠EPA = ∠DPB
P is the mid point of AB
∴AP = BP
TO PROVE:
(i) ΔDAP≅ ΔEBP
(ii) AD = BE
PROOF: In ΔDAP and ΔEBP
∠BAD = ∠ABE(given)
∠EPA=∠DPB(given)
Adding ∠EPD both sides
∠EPA +∠EPD =∠DPB+ ∠EPD
∠APD = ∠EPB
AP = BP(given)
ΔDAP≅ ΔEBP(ASA rule)
Q8.In right triangle ABC ,right angled at C , M is th mid point of hypotenuse AB, C is
joined to M and produced to a point D such that DM = CM . Point D is joined to point
B(see the given figure). Show that
(i) ΔAMC ≅ BMD
(ii) ∠DBC is a right angle
(iii) ΔDBC ≅ ΔACB
Ans.
(i) GIVEN:ΔABC is a right triagle ,∠C = 90°
M is the midpoint of AB
∴BM = AM
AM = AB/2
DM = CM
TO PROVE: ΔAMC ≅ BMD
PROOF:DM = CM (given)
BM = AM (given)
∠BMD = ∠AMC (Vertically opposite angle)
ΔAMC ≅ BMD(SAS rule)
Hence proved
(ii) Since ΔAMC ≅ BMD(proved)
∠DBM = ∠CAM (By CPCT)
∠DBM and ∠CAM are alternate angles
∴DB ∥ AC
∠DBC + ∠ACB = 180°(co-interior angles)
∠ACB = 90°
∠DBC + 90°= 180°
∠DBC = 90°
Hence proved
(iii) Since ΔAMC ≅ BMD(proved)
BD = AC (By CPCT)
BC = BC(common)
∠DBC = ∠ACB =90°
(Proved above)
ΔDBC ≅ ΔACB (SAS rule)
proved above
(iv) CM = DM(given)
CM + DM = DC
CM + CM = DC
2CM = DC
CM = 1/2 DC
Since we have proved
ΔDBC ≅ ΔACB
So, DC = AB (by CPCT)
Therefore
CM = 1/2 AB
Hence proved
Exercise 7.2
Q1.In an isosceles triangle ABC, with AB = AC, the bisector of angle ∠B and ∠C, intersect
each other at O. Join A to O. Show that:
(i) OB = OC (ii) AO bisects ∠A
Ans.
GIVEN: In ΔABC
AB = AC
BO is bisector of ∠B and CO is bisector of ∠C
TO PROVE:(i) OB = OC (ii) AO bisects ∠A
PROOF:In ΔABC
AB = AC (given)
∠ABC = ∠ACB (angles opposite to equal sides)
It is given to us that BO is bisector of ∠B and CO is bisector of ∠C
1/2(∠ABC) = 1/2(∠ACB)
∠OBC = ∠OCB
OB = OC (sides opposite to equal angles)
Hence proved
(ii) OB = OC (proved above)
AO = AO (common)
AB = AC (given)
ΔABO ≅ΔACO (SSS rule)
∠OAB = ∠OCA (by CPCT)
Therefore AO is the bisector of ∠A.
Hence proved
Q2. In ΔABC , AD is perpendicular bisector of BC (see the given figure). Show that
ΔABC is an isoscles triangle in which AB = AC.
Ans.
GIVEN: In ΔABC , AD is perpendicular bisector of BC
∴ BD = DC
∠ADB = ∠ADC = 90°
TO PROVE: AB = AC
PROOF: In ΔABD and ΔACD
∠ADB = ∠ADC = 90°
(given)
AD = AD (common)
BD = DC(given)
ΔABD ≅ ΔACD (SAS rule)
AB = AC(by CPCT)
Hence ΔABC is an isosceles triangle in which AB = AC
Q3. ABC is an isoscles triangle in which altitudes BE and CF are drawn to equal sides AC
and AB respectively (see the given figure).Show that these altitudes are equal.
Ans.
GIVEN: ΔABC in which AC = AB
CF ⊥ AB and CE ⊥ AC
∴∠AFC = ∠AEB = 90°
TO PROVE: CF = BE
PROOF: AC = AB (given)
∠AFC = ∠AEB = 90°
(given)
∠A = ∠A (common)
ΔAEB ≅ AFC (AAS rule)
BE = CF(by CPCT)
Hence proved
Q4.ABC is a triangle in which altitudes BE and CF to sides AC and AB are equal (see the
given figure). Show that.
(i) ΔABE ≅ ACF
(ii)AB = AC i.e ABC is an isosceles triangle
Ans.
GIVEN: ΔABC in which BE = CF
CF ⊥ AB and CE ⊥ AC
∴∠AFC = ∠AEB = 90°
TO PROVE: AC = AB
(i) PROOF:BE = CF (given)
∠AFC = ∠AEB = 90°
(given)
∠A = ∠A (common)
ΔAEB ≅ AFC (AAS rule)
(ii) AC = AB (by CPCT)
Hence proved
Q5. ABC and DBC are two isosceles triangles on the same base BC (see the given figure).
Show that ∠ABD = ∠ACD.
Ans.
GIVEN: ΔABC in which AB = AC
ΔDBC in which BD = DC
TO PROVE: ∠ABD = ∠ACD
PROOF: In Δ ABC
AB = AC (given)
∠ABC = ∠ACB ....(i) (angles opposite to equal sides)
BD = DC
∠DBC = ∠DCB....(ii) (angles opposite to equal sides)
Adding equation (i) and (ii)
∠ABC + ∠DBC = ∠ACB + ∠DCB
∠ABD = ∠ACD
Hence proved
Q6. ΔABC is an isosceles triangle in which AB = AC, side BA is produced to D such that
AD = AB(see the given figure). Show that ∠BCD is a right angle.
Ans.
GIVEN:AB = AC
AD = AB
TO PROVE: ∠BCD = 90°
PROOF : AB = AC (given)
∠ABC = ∠ACB (angles opposite to equal sides)
Applying the angle sum property in ΔABC
∠ABC + ∠BAC + ∠ACB = 180°
∠BAC = 180°
- (∠ABC + ∠ACB)
∠BAC and ∠DAC are lienear pair
So, ∠BAC + ∠DAC = 180°
180°
- (∠ABC + ∠ACB) + ∠DAC = 180°
∠DAC = ∠ABC + ∠ACB =∠ACB + ∠ACB =2∠ACB
∠ACB = 1/2 ∠DAC.....(i)
AD = AC (given)
∠ADC = ∠ACD (angles opposite to equal sides)
Applying the angle sum property in ΔABC
∠ADC + ∠ACD + ∠DAC = 180°
∠ACD + ∠ACD + ∠DAC = 180°
2∠ACD + ∠DAC = 180°
∠DAC = 180°- 2∠ACD
∠ACD = 90°- 1/2 ∠DAC........(ii)
Adding equation (i) and (ii)
∠ACB + ∠ACD = 1/2 ∠DAC+ 90°- 1/2 ∠DAC
∠BCD = 90°
Hence ΔBCD is right triangle
Q7. ABC is a right triangle in which ∠A = 90°and AB = AC. Find ∠B and ∠C.
Ans.
We are given triagle ABC in which
∠A = 90°
AB = AC
∠B = ∠C (angles opposite to equal sides)
∠B + ∠C + ∠A = 180°
∠B + ∠B +90°= 180°
2∠B + 90°= 180°
2∠B = 90°
∠B = 45°
∠C = 45°
Hence both of the angles ∠B and ∠C are of 45°
Q8. Show that the angles of an equilateral triangle are 60°each.
Ans.
We are given that ΔABC is an equilateral triangle
AB = AC (sides of equilateral triangle)
∠C = ∠B .....(i)(angles opposite to equal sides)
BC = AC (sides of equilateral triangle)
∠B = ∠A .....(ii)(angles opposite to equal sides)
From equation (i) and (ii)
∠A = ∠B = ∠C
Applying angle sum property of the triangle in ΔABC
∠A +∠B +∠C = 180°
∠A + ∠A + ∠A = 180°
3∠A = 180°
∠A = 180°
/3
∠A = 60°
∴∠A = ∠B =∠C=60°
Therefore angles of an equilateral triangle are 60°each.
Exercise 7.3
Q1. ΔABC and ΔDBC are two isosceles on the same base BC and vertices A and D are on
the same side of BC (see the given figure). If AD is extended to intersect BC at P, show that
(i) ΔABD ≅ ACD
(ii)ΔABP ≅ ACP
(iii)AP bisects ∠A and as well as ∠D
(iv) AP is the perpendicular bisector of BC
Ans.
GIVEN: ΔABC and ΔDBC are two isosceles with a common base BC
In which AB = AC and AD = DC
(i) TO PROVE: ΔABD ≅ ACD
PROOF:AB = AC (given)
BD = CD (given)
AD = AD (common)
ΔABD ≅ ACD (SSS rule)
Hence proved
(ii) TO PROVE:ΔABP ≅ ACP
PROOF: AB = AC (given)
AP = AP(common)
Since we have already proved ΔABD ≅ ACD
∴∠BAP = ∠PAC (By CPCT)
ΔABP ≅ ACP(SAS rule)
Hence proved
(iii TO PROVE: AP bisects ∠A and as well as ∠D
PROOF:In ΔDPB and ΔDPC
Since we have proved ΔABD ≅ ACD and ΔABP ≅ ACP
∴ BD = DC (By CPCT) and BP = PC (CPCT)
DP = DP (common)
ΔDPB ≅ΔDPC
∠DPB =∠DPC (By CPCT)...(i)
And it is already proved ΔABD ≅ ACD
∠BAD=∠DAC (By CPCT)....(*ii)
From (i) and (ii) it is clear that AP bisects ∠A and as well as ∠D
Hence proved
(iv) TO PROVE: AP is the perpendicular bisector of BC
PROOF: Since we have proved ΔABP ≅ ACP
Therefore ∠APB = ∠APC (By CPCT)
BP = PC(By CPCT).....(i)
∠APB + ∠APC = 180°
∠APB +∠APB = 180°
2 ∠APB = 180°
∠APB = 90°
∴ AP ⊥ BC......(ii)
From (i) and (ii), it is cleared that AP is a perpendicular bisector of BC
Hence proved
Q2.AD is an altitude of an isosceles triangle ABC in which AB = AC. Show that (i) AD
bisects BC (ii) AD bisects ∠A.
Ans.
GIVEN: An isosceles triangle ΔABC in which AB = AC
AD is the altitude of the isosceles triangle
∴ ∠ADC = ∠ADB = 90°
TO PROVE: (i) AD bisects BC
In ΔABD and ΔACD
AD = AD (common)
AB = AC (given)
∠ADC = ∠ADB = 90°(AD ⊥ BC)
ΔABD ≅ ΔACD(RHS rule)
BD = DC (By CPCT)
Hence AD bisects BC
(ii) TO PROVE: AD bisects ∠A.
Since we have proved ΔABD ≅ ΔACD
∴∠BAD = ∠DAC (By CPCT)
Therefore AD bisects ∠A
Q3. Two sides AB and BC and median AM of one triangle ABC are respectively equal to
sides PQ and QR and median PN of ΔPQR see the given figure. Show that.
(i) ΔABM ≅Δ PQN
(ii)ΔABC ≅ ΔPQR
Ans.
GIVEN: In ΔABC and ΔPQR
AB = PQ
BC = QR
AM = PN
TO PROVE: (i) ΔABM ≅Δ PQN
PROOF: AB = PQ (given)
AM = PN (given)
BC = QR (given)
Since AM is the median of the triangle ΔABC and PN is the median of the triangle ΔPQR
∴BC/2 = QR/2
BM = QN
ΔABM ≅Δ PQN (SSS rule)
Hence proved
TO PROVE (ii)ΔABC ≅ ΔPQR
PROOF: Since we have already proved ΔABM ≅Δ PQN
∴∠ABM = ∠PQN (by CPCT)
AB = PQ (given)
BC = QR(given)
ΔABM ≅Δ PQN (SAS rule)
Hence proved
Q4. BE and CF are two equal altitudes of a triangle ABC. Using the RHS congruence rule,
prove that the triangle ABC is isosceles.
Ans.
GIVEN: In ΔABC, in which two altitudes BE and CF are equal
BE = CF
∠CFB = ∠CEB = 90°
TO PROVE: triangle ABC is isosceles
In ΔCFB and ΔBEC
The hypotenuse of both right triangles is common
BC = BC (common)
∠CFB = ∠CEB = 90°
(BE and CF are altitudes of both triangles)
BE = CF (equal)
ΔΔCFB≅ ΔBEC (RHS rule)
∠B = ∠C (by CPCT)
AB = AC (opposite sides of equal triangles)
Q5. ABC is an isoscles triangle with AB = AC . Draw AP⊥ BC to show that ∠B = ∠C.
Ans.
GIVEN: In triangle ABP and triangle ACP
AB = AC
∠APB = ∠APC = 90°(AP ⊥ BC)
TO PROVE:∠B = ∠C
PROOF: In ΔABP and ΔACP
AB = AC (given)
AP = AP (common)
∠APB = ∠APC = 90°
(given)
ΔABP ≅ ΔACP (RHS rule)
∠B = ∠C (by CPCT)
Hence proved
Q1.Show that in a right-angled triangle, the hypotenuse is the longest triangle.
Ans.
GIVEN: ΔABC is a right triangle,let ∠B =90°
TO PROVE: Hypotenuse is the largest side in a right triangle
PROOF: ∠B = 90°
(given)
∠A + ∠B + ∠C = 180°(angle sum property of the triangle)
∠A + 90°+ ∠C = 180°
∠A + ∠C = 180°
-90°
= 90°
∠A and ∠C must be acute angle
∴∠A < 90°and ∠C < 90°
Therefore ∠B is the largest angle
So, ∠B >∠A and ∠B>∠C
AC> BC and AC > AB (in a triangle side opposite to larger angle is longer)
Hence AC(hypotenuse) is the largest side in a right triangle
Q2.In the given figure sides AB and AC of ΔABC are extended to points P and Q
respectively .Also ∠PBC < ∠QCB. Show that AC > AB.
Ans.
GIVEN: In the fig. ∠PBC < ∠QCB
TO PROVE:AC > AB
PROOF: ∠PBC < ∠QCB(given)
∠ABC + ∠PBC = 180°
(linear pair)
∠PBC = 180°- ∠ABC ....(i)
∠ACB + ∠QCB = 180°
(linear pair)
∠QCB = 180°- ∠ACB ....(ii)
From equation (i) and equation (ii)
180°- ∠ABC < 180°- ∠ACB
∠ABC >∠ ACB
AC > AB (side opposite to larger angle is greater)
Q3.In the given figure , ∠B < ∠A, and ∠C < ∠D. Show that AD < BC.
Ans.
GIVEN: ∠B < ∠A, and ∠C < ∠D
TO PROVE:AD < BC
PROOF: ∠B < ∠A (given)
OA < OB....(i) (side opposite to larger angle is grater)
∠C < ∠D
OD < OC...(ii) (side opposite to larger angle is grater)
From equation (i) and equation (ii)
OA + OD < OB + OC
AD < BC (from figure), Hence proved
Q4.AB and CD are respectively smallest and the longest side of quadrilateral ABCD(see the
given figure). Show that ∠A > ∠C and ∠B > ∠D.
Ans.
GIVEN: AB and CD are respectively smallest and the longest side of quadrilateral ABCD
COSTRUCTION: Joining A to C and B to D
TO PROVE: (i) ∠A > ∠C (ii) ∠B > ∠D.
(i) PROOF: In ΔABC
BC> AB (AB is the smallest side in ABCD)
∠BAC > ∠ACB ....(i) (side opposite to larger angle is grater)
In ΔADC
CD > AD (CD is the largest side in ABCD)
∠DAC > ∠ACD....(ii)
Adding equation (i) and (ii)
∠BAC + ∠DAC > ∠ACB + ∠ACD
∠A > ∠C, Hence proved
PROOF: (ii) ∠B > ∠D
In ΔABD
AD> AB (AB is the smallest side in ABCD)
∠ABD > ∠ADB ....(i) (side opposite to larger angle is grater)
In ΔADC
CD > BC (CD is the largest side in ABCD)
∠DBC > ∠BDC....(ii)
Adding equation (i) and (ii)
∠ABD +∠DBC > ∠ADB + ∠BDC
∠B > ∠D, Hence proved
Q5.In the given figure , PR > PQ and PS bisects ∠QPR , prove that ∠PSR > PSQ.
Ans.
GIVEN:PR > PQ
PS bisects ∠QPR
∠QPS = ∠SPR
TO PROVE: ∠PSR >∠ PSQ
PROOF: PR > PQ (given)
∠Q > ∠R (side opposite to larger angle is grater)
In ΔPQS
∠Q + ∠QPS + ∠ PSQ = 180°
(angle sum property of the triangle)
∠Q = 180°-(∠QPS + ∠ PSQ).....(i)
In ΔPSR
∠R + ∠SPR + ∠ PSR = 180°
(angle sum property of the triangle)
∠R = 180°-(∠SPR + ∠ PSR).....(ii)
From (i) and (ii)
180°-(∠QPS + ∠ PSQ) > 180°-(∠SPR + ∠ PSR)
∠SPR + ∠ PSR >∠QPS + ∠ PSQ
Since PS bisects ∠P, ∠QPS = ∠SPR
∠SPR + ∠ PSR >∠SPR + ∠ PSQ
∠ PSR >∠ PSQ, Hence proved
Q6. Show that of all line segments drawn from a given point not on it, the perpendicular
line segment is the shortest.
Ans. Let A is an external point out of the line and AC⊥ BC
Let BC is a line and AB is a line segment drawn from the point A on the line BC
In triangle ΔABC
∠B <∠C (since ∠B is acute angle and ∠C =90°
)
AC < AB (side opposite to larger angle is grater)
Similarly all line segments drawn from A on the line BC are larger than AC
Therefore AC is the shortest side drawn from A on BC, Hence proved
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NCERT Solutions of Class 9 Science : Chapter 1 to Chapter 15
Class 9-Sample papers and question papers
Mid point theorem
Solutions of important question papers of last year's question papers
Mean,mode median
Solutions of specific questions of mensuration
How to write linear equation in two variable
Technics of achieving hundred percent marks in Maths
Maths assignments for class 9 and 10
9 class maths assignment for SA-1
Lines,angles and Triangles
Addition, subtraction,multiplication and division of polynomial
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Class 9 Science NCERT solutions and science notes
Chemistry
Lesson 1-Matter in our surroundings
Chapter 2- Is matter around us pure
Chapter 3-Atoms and Molecules
Lesson 4-Structure of the Atoms
Biology
Chapter 5- Fundamental Unit of Life
Physics
Chapter 8 -Motion
Chapter 9 - Force and Laws of Motion
Chapter 10- Gravitation
Chapter 11-Work and Energy
Lesson 12 - Sound
Study science notes
Archimedes Principle: Complete detail
Average Speed and Average velocity
Three equation of Motions
Recoil velocity of the gun
Mole concept
The second law of motion
The universal law of gravitational force
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Exercise 8.1-Application of Integrals
Exercise 8.2-Application of Integrals
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Triangles class 9

  • 1. Triangles: NCERT Class 9 CBSE Exercise 7.1 Q1.In quadrilateral ACBD, AC = AD, and AB bisect ∠A (see the given figure). Show that ΔABC≅ΔABD. What can you say about BC and BD? Ans. GIVEN:In quadrilateral ACBD, AC = AD AB is the bisector of ∠A So, ∠BAC = ∠DAB TO PROVE: ΔABC≅ΔABD PROOF: In ΔABC and ΔABD We have AC = AD (given) AB = AB (common) ∠BAC = ∠DAB (given) ΔABC≅ΔABD (SAS rule) BC = BD (by CPCT) Q2. ABCD is a quadrilateral in which AD = BC and ∠DAB = ∠CBA (see the given figure ).Prove that
  • 2. (i) ΔABD ≅ΔBAC (ii) BD = AC (iii) ∠ABD = ∠BAC Ans. (i) GIVEN: ABCD is a quadrilateral AD = BC and ∠DAB = ∠CBA TO PROVE: ΔABD ≅ΔBAC PROOF: In ΔABD and ΔBAC AD = BC (given) AB = AB (common) ∠DAB = ∠CBA ΔABD ≅ΔBAC (SAS) Hence proved (ii) BD = AC (By CPCT) (iii) ∠ABD = ∠BAC(By CPCT) Q3. AD and BC are equal perpendiculars to a line segment AB (see the given figure).Show that CD bisects AB.
  • 3. Ans. GIVEN: AD = BC AB ⊥ BC and AB ⊥ BC ∴∠OBC = ∠OAD = 90° TO PROVE: CD bisects AB i.e AO = BO PROOF: In ΔAOD and ΔBOD Since BOA and COD is a line ∠DOA = ∠BOC (vertically opposite angle) AD = BC (Given) ∠OBC = ∠OAD = 90° (given) ΔBOC ≅ ΔAOD(AAS) AO = BO (By CPCT) Hence Proved Q4. l and m are two parallel lines intersected by another pair of parallel lines p and q(see the given figure). Show that ΔABC ≅ CDA.
  • 4. Ans. GIVEN: p ∥ q and l∥ m TO PROVE: ΔABC ≅ ΔCDA PROOF:In the figure l∥ m and AC is the transversal(given) So, ∠DAC = ∠ACB (alternate angles) p ∥ q and AC is the transversal(given) ∠BAC = ∠ACD(alternate angles) AC = AC(given) ΔABC ≅ Δ CDA(ASA rule) Hence proved Q5.Line l is the bisector of an angle ∠A and B is any point on l ,BP and BQ are perpendiculars from B to the arms of ∠A(see the given figure). Show that (i) ΔAPB ≅ΔAQB (ii) BP = BQ or B is equidistant from the arms of ∠A
  • 5. Ans. (i) GIVEN: ,BP and BQ are perpendiculars from B to the arms of ∠A ∴∠AQB = ∠APB = 90° Line l is the bisector of an angle ∠A and ∴∠QAB = ∠PAB TO PROVE: ΔAPB ≅ΔAQB PROOF:∠AQB = ∠APB = 90° (given) AB = AB (common) ∠QAB = ∠PAB (given) ΔAPB ≅ΔAQB (AAS rule) (ii) BP = BQ(by CPCT) Hence proved Q6. In the given figure, AC = AE, AB = AD and ∠BAD = ∠EAC. Show that BC =DE.
  • 6. Ans. GIVEN: AC = AE AB = AD ∠BAD = ∠EAC TO PROVE: BC =DE PROOF: We have to prove BC =DE, which are sides of the triangle ΔABC and ΔADE In triangles ΔABC and ΔADE AB = AD(given) AC = AE(given) ∠BAD = ∠EAC (given) Adding both sides ∠DAC ∠BAD + ∠DAC = ∠EAC + ∠DAC ∠BAC = ∠DAE(proved) ΔABC ≅ ΔADE (SAS rule) BC = DE (by CPCT ) Hence proved Q7. AB is a line segment and p is its midpoint. D and E are points on the same sides of AB such that ∠BAD = ∠ABE and ∠EPA=∠DPB(see the given figure). Show that
  • 7. (i) ΔDAP≅ ΔEBP (ii) AD = BE Ans.(i) GIVEN: ∠DAP = ∠EBP ∠EPA = ∠DPB P is the mid point of AB ∴AP = BP TO PROVE: (i) ΔDAP≅ ΔEBP (ii) AD = BE PROOF: In ΔDAP and ΔEBP ∠BAD = ∠ABE(given) ∠EPA=∠DPB(given) Adding ∠EPD both sides ∠EPA +∠EPD =∠DPB+ ∠EPD ∠APD = ∠EPB AP = BP(given)
  • 8. ΔDAP≅ ΔEBP(ASA rule) Q8.In right triangle ABC ,right angled at C , M is th mid point of hypotenuse AB, C is joined to M and produced to a point D such that DM = CM . Point D is joined to point B(see the given figure). Show that (i) ΔAMC ≅ BMD (ii) ∠DBC is a right angle (iii) ΔDBC ≅ ΔACB Ans. (i) GIVEN:ΔABC is a right triagle ,∠C = 90° M is the midpoint of AB ∴BM = AM AM = AB/2 DM = CM TO PROVE: ΔAMC ≅ BMD PROOF:DM = CM (given) BM = AM (given)
  • 9. ∠BMD = ∠AMC (Vertically opposite angle) ΔAMC ≅ BMD(SAS rule) Hence proved (ii) Since ΔAMC ≅ BMD(proved) ∠DBM = ∠CAM (By CPCT) ∠DBM and ∠CAM are alternate angles ∴DB ∥ AC ∠DBC + ∠ACB = 180°(co-interior angles) ∠ACB = 90° ∠DBC + 90°= 180° ∠DBC = 90° Hence proved (iii) Since ΔAMC ≅ BMD(proved) BD = AC (By CPCT) BC = BC(common) ∠DBC = ∠ACB =90° (Proved above) ΔDBC ≅ ΔACB (SAS rule) proved above (iv) CM = DM(given) CM + DM = DC CM + CM = DC 2CM = DC CM = 1/2 DC
  • 10. Since we have proved ΔDBC ≅ ΔACB So, DC = AB (by CPCT) Therefore CM = 1/2 AB Hence proved Exercise 7.2 Q1.In an isosceles triangle ABC, with AB = AC, the bisector of angle ∠B and ∠C, intersect each other at O. Join A to O. Show that: (i) OB = OC (ii) AO bisects ∠A Ans. GIVEN: In ΔABC AB = AC BO is bisector of ∠B and CO is bisector of ∠C TO PROVE:(i) OB = OC (ii) AO bisects ∠A PROOF:In ΔABC AB = AC (given)
  • 11. ∠ABC = ∠ACB (angles opposite to equal sides) It is given to us that BO is bisector of ∠B and CO is bisector of ∠C 1/2(∠ABC) = 1/2(∠ACB) ∠OBC = ∠OCB OB = OC (sides opposite to equal angles) Hence proved (ii) OB = OC (proved above) AO = AO (common) AB = AC (given) ΔABO ≅ΔACO (SSS rule) ∠OAB = ∠OCA (by CPCT) Therefore AO is the bisector of ∠A. Hence proved Q2. In ΔABC , AD is perpendicular bisector of BC (see the given figure). Show that ΔABC is an isoscles triangle in which AB = AC. Ans. GIVEN: In ΔABC , AD is perpendicular bisector of BC
  • 12. ∴ BD = DC ∠ADB = ∠ADC = 90° TO PROVE: AB = AC PROOF: In ΔABD and ΔACD ∠ADB = ∠ADC = 90° (given) AD = AD (common) BD = DC(given) ΔABD ≅ ΔACD (SAS rule) AB = AC(by CPCT) Hence ΔABC is an isosceles triangle in which AB = AC Q3. ABC is an isoscles triangle in which altitudes BE and CF are drawn to equal sides AC and AB respectively (see the given figure).Show that these altitudes are equal. Ans. GIVEN: ΔABC in which AC = AB CF ⊥ AB and CE ⊥ AC ∴∠AFC = ∠AEB = 90°
  • 13. TO PROVE: CF = BE PROOF: AC = AB (given) ∠AFC = ∠AEB = 90° (given) ∠A = ∠A (common) ΔAEB ≅ AFC (AAS rule) BE = CF(by CPCT) Hence proved Q4.ABC is a triangle in which altitudes BE and CF to sides AC and AB are equal (see the given figure). Show that. (i) ΔABE ≅ ACF (ii)AB = AC i.e ABC is an isosceles triangle Ans. GIVEN: ΔABC in which BE = CF CF ⊥ AB and CE ⊥ AC ∴∠AFC = ∠AEB = 90° TO PROVE: AC = AB (i) PROOF:BE = CF (given) ∠AFC = ∠AEB = 90° (given)
  • 14. ∠A = ∠A (common) ΔAEB ≅ AFC (AAS rule) (ii) AC = AB (by CPCT) Hence proved Q5. ABC and DBC are two isosceles triangles on the same base BC (see the given figure). Show that ∠ABD = ∠ACD. Ans. GIVEN: ΔABC in which AB = AC ΔDBC in which BD = DC TO PROVE: ∠ABD = ∠ACD PROOF: In Δ ABC AB = AC (given) ∠ABC = ∠ACB ....(i) (angles opposite to equal sides) BD = DC ∠DBC = ∠DCB....(ii) (angles opposite to equal sides) Adding equation (i) and (ii) ∠ABC + ∠DBC = ∠ACB + ∠DCB
  • 15. ∠ABD = ∠ACD Hence proved Q6. ΔABC is an isosceles triangle in which AB = AC, side BA is produced to D such that AD = AB(see the given figure). Show that ∠BCD is a right angle. Ans. GIVEN:AB = AC AD = AB TO PROVE: ∠BCD = 90° PROOF : AB = AC (given) ∠ABC = ∠ACB (angles opposite to equal sides) Applying the angle sum property in ΔABC ∠ABC + ∠BAC + ∠ACB = 180° ∠BAC = 180° - (∠ABC + ∠ACB) ∠BAC and ∠DAC are lienear pair So, ∠BAC + ∠DAC = 180° 180° - (∠ABC + ∠ACB) + ∠DAC = 180° ∠DAC = ∠ABC + ∠ACB =∠ACB + ∠ACB =2∠ACB ∠ACB = 1/2 ∠DAC.....(i)
  • 16. AD = AC (given) ∠ADC = ∠ACD (angles opposite to equal sides) Applying the angle sum property in ΔABC ∠ADC + ∠ACD + ∠DAC = 180° ∠ACD + ∠ACD + ∠DAC = 180° 2∠ACD + ∠DAC = 180° ∠DAC = 180°- 2∠ACD ∠ACD = 90°- 1/2 ∠DAC........(ii) Adding equation (i) and (ii) ∠ACB + ∠ACD = 1/2 ∠DAC+ 90°- 1/2 ∠DAC ∠BCD = 90° Hence ΔBCD is right triangle Q7. ABC is a right triangle in which ∠A = 90°and AB = AC. Find ∠B and ∠C. Ans. We are given triagle ABC in which ∠A = 90° AB = AC
  • 17. ∠B = ∠C (angles opposite to equal sides) ∠B + ∠C + ∠A = 180° ∠B + ∠B +90°= 180° 2∠B + 90°= 180° 2∠B = 90° ∠B = 45° ∠C = 45° Hence both of the angles ∠B and ∠C are of 45° Q8. Show that the angles of an equilateral triangle are 60°each. Ans. We are given that ΔABC is an equilateral triangle AB = AC (sides of equilateral triangle) ∠C = ∠B .....(i)(angles opposite to equal sides) BC = AC (sides of equilateral triangle) ∠B = ∠A .....(ii)(angles opposite to equal sides) From equation (i) and (ii)
  • 18. ∠A = ∠B = ∠C Applying angle sum property of the triangle in ΔABC ∠A +∠B +∠C = 180° ∠A + ∠A + ∠A = 180° 3∠A = 180° ∠A = 180° /3 ∠A = 60° ∴∠A = ∠B =∠C=60° Therefore angles of an equilateral triangle are 60°each. Exercise 7.3 Q1. ΔABC and ΔDBC are two isosceles on the same base BC and vertices A and D are on the same side of BC (see the given figure). If AD is extended to intersect BC at P, show that (i) ΔABD ≅ ACD (ii)ΔABP ≅ ACP (iii)AP bisects ∠A and as well as ∠D (iv) AP is the perpendicular bisector of BC Ans.
  • 19. GIVEN: ΔABC and ΔDBC are two isosceles with a common base BC In which AB = AC and AD = DC (i) TO PROVE: ΔABD ≅ ACD PROOF:AB = AC (given) BD = CD (given) AD = AD (common) ΔABD ≅ ACD (SSS rule) Hence proved (ii) TO PROVE:ΔABP ≅ ACP PROOF: AB = AC (given) AP = AP(common) Since we have already proved ΔABD ≅ ACD ∴∠BAP = ∠PAC (By CPCT) ΔABP ≅ ACP(SAS rule) Hence proved (iii TO PROVE: AP bisects ∠A and as well as ∠D PROOF:In ΔDPB and ΔDPC Since we have proved ΔABD ≅ ACD and ΔABP ≅ ACP ∴ BD = DC (By CPCT) and BP = PC (CPCT) DP = DP (common) ΔDPB ≅ΔDPC ∠DPB =∠DPC (By CPCT)...(i)
  • 20. And it is already proved ΔABD ≅ ACD ∠BAD=∠DAC (By CPCT)....(*ii) From (i) and (ii) it is clear that AP bisects ∠A and as well as ∠D Hence proved (iv) TO PROVE: AP is the perpendicular bisector of BC PROOF: Since we have proved ΔABP ≅ ACP Therefore ∠APB = ∠APC (By CPCT) BP = PC(By CPCT).....(i) ∠APB + ∠APC = 180° ∠APB +∠APB = 180° 2 ∠APB = 180° ∠APB = 90° ∴ AP ⊥ BC......(ii) From (i) and (ii), it is cleared that AP is a perpendicular bisector of BC Hence proved Q2.AD is an altitude of an isosceles triangle ABC in which AB = AC. Show that (i) AD bisects BC (ii) AD bisects ∠A. Ans.
  • 21. GIVEN: An isosceles triangle ΔABC in which AB = AC AD is the altitude of the isosceles triangle ∴ ∠ADC = ∠ADB = 90° TO PROVE: (i) AD bisects BC In ΔABD and ΔACD AD = AD (common) AB = AC (given) ∠ADC = ∠ADB = 90°(AD ⊥ BC) ΔABD ≅ ΔACD(RHS rule) BD = DC (By CPCT) Hence AD bisects BC (ii) TO PROVE: AD bisects ∠A. Since we have proved ΔABD ≅ ΔACD ∴∠BAD = ∠DAC (By CPCT) Therefore AD bisects ∠A Q3. Two sides AB and BC and median AM of one triangle ABC are respectively equal to sides PQ and QR and median PN of ΔPQR see the given figure. Show that. (i) ΔABM ≅Δ PQN (ii)ΔABC ≅ ΔPQR
  • 22. Ans. GIVEN: In ΔABC and ΔPQR AB = PQ BC = QR AM = PN TO PROVE: (i) ΔABM ≅Δ PQN PROOF: AB = PQ (given) AM = PN (given) BC = QR (given) Since AM is the median of the triangle ΔABC and PN is the median of the triangle ΔPQR ∴BC/2 = QR/2 BM = QN ΔABM ≅Δ PQN (SSS rule) Hence proved TO PROVE (ii)ΔABC ≅ ΔPQR
  • 23. PROOF: Since we have already proved ΔABM ≅Δ PQN ∴∠ABM = ∠PQN (by CPCT) AB = PQ (given) BC = QR(given) ΔABM ≅Δ PQN (SAS rule) Hence proved Q4. BE and CF are two equal altitudes of a triangle ABC. Using the RHS congruence rule, prove that the triangle ABC is isosceles. Ans. GIVEN: In ΔABC, in which two altitudes BE and CF are equal BE = CF ∠CFB = ∠CEB = 90° TO PROVE: triangle ABC is isosceles In ΔCFB and ΔBEC The hypotenuse of both right triangles is common BC = BC (common) ∠CFB = ∠CEB = 90° (BE and CF are altitudes of both triangles) BE = CF (equal) ΔΔCFB≅ ΔBEC (RHS rule)
  • 24. ∠B = ∠C (by CPCT) AB = AC (opposite sides of equal triangles) Q5. ABC is an isoscles triangle with AB = AC . Draw AP⊥ BC to show that ∠B = ∠C. Ans. GIVEN: In triangle ABP and triangle ACP AB = AC ∠APB = ∠APC = 90°(AP ⊥ BC) TO PROVE:∠B = ∠C PROOF: In ΔABP and ΔACP AB = AC (given) AP = AP (common) ∠APB = ∠APC = 90° (given) ΔABP ≅ ΔACP (RHS rule)
  • 25. ∠B = ∠C (by CPCT) Hence proved Q1.Show that in a right-angled triangle, the hypotenuse is the longest triangle. Ans. GIVEN: ΔABC is a right triangle,let ∠B =90° TO PROVE: Hypotenuse is the largest side in a right triangle PROOF: ∠B = 90° (given) ∠A + ∠B + ∠C = 180°(angle sum property of the triangle) ∠A + 90°+ ∠C = 180° ∠A + ∠C = 180° -90° = 90° ∠A and ∠C must be acute angle ∴∠A < 90°and ∠C < 90°
  • 26. Therefore ∠B is the largest angle So, ∠B >∠A and ∠B>∠C AC> BC and AC > AB (in a triangle side opposite to larger angle is longer) Hence AC(hypotenuse) is the largest side in a right triangle Q2.In the given figure sides AB and AC of ΔABC are extended to points P and Q respectively .Also ∠PBC < ∠QCB. Show that AC > AB. Ans. GIVEN: In the fig. ∠PBC < ∠QCB TO PROVE:AC > AB PROOF: ∠PBC < ∠QCB(given) ∠ABC + ∠PBC = 180° (linear pair) ∠PBC = 180°- ∠ABC ....(i) ∠ACB + ∠QCB = 180° (linear pair) ∠QCB = 180°- ∠ACB ....(ii) From equation (i) and equation (ii) 180°- ∠ABC < 180°- ∠ACB ∠ABC >∠ ACB AC > AB (side opposite to larger angle is greater)
  • 27. Q3.In the given figure , ∠B < ∠A, and ∠C < ∠D. Show that AD < BC. Ans. GIVEN: ∠B < ∠A, and ∠C < ∠D TO PROVE:AD < BC PROOF: ∠B < ∠A (given) OA < OB....(i) (side opposite to larger angle is grater) ∠C < ∠D OD < OC...(ii) (side opposite to larger angle is grater) From equation (i) and equation (ii) OA + OD < OB + OC AD < BC (from figure), Hence proved Q4.AB and CD are respectively smallest and the longest side of quadrilateral ABCD(see the given figure). Show that ∠A > ∠C and ∠B > ∠D.
  • 28. Ans. GIVEN: AB and CD are respectively smallest and the longest side of quadrilateral ABCD COSTRUCTION: Joining A to C and B to D TO PROVE: (i) ∠A > ∠C (ii) ∠B > ∠D. (i) PROOF: In ΔABC BC> AB (AB is the smallest side in ABCD) ∠BAC > ∠ACB ....(i) (side opposite to larger angle is grater) In ΔADC CD > AD (CD is the largest side in ABCD) ∠DAC > ∠ACD....(ii) Adding equation (i) and (ii) ∠BAC + ∠DAC > ∠ACB + ∠ACD ∠A > ∠C, Hence proved PROOF: (ii) ∠B > ∠D In ΔABD AD> AB (AB is the smallest side in ABCD) ∠ABD > ∠ADB ....(i) (side opposite to larger angle is grater)
  • 29. In ΔADC CD > BC (CD is the largest side in ABCD) ∠DBC > ∠BDC....(ii) Adding equation (i) and (ii) ∠ABD +∠DBC > ∠ADB + ∠BDC ∠B > ∠D, Hence proved Q5.In the given figure , PR > PQ and PS bisects ∠QPR , prove that ∠PSR > PSQ. Ans. GIVEN:PR > PQ PS bisects ∠QPR ∠QPS = ∠SPR TO PROVE: ∠PSR >∠ PSQ PROOF: PR > PQ (given)
  • 30. ∠Q > ∠R (side opposite to larger angle is grater) In ΔPQS ∠Q + ∠QPS + ∠ PSQ = 180° (angle sum property of the triangle) ∠Q = 180°-(∠QPS + ∠ PSQ).....(i) In ΔPSR ∠R + ∠SPR + ∠ PSR = 180° (angle sum property of the triangle) ∠R = 180°-(∠SPR + ∠ PSR).....(ii) From (i) and (ii) 180°-(∠QPS + ∠ PSQ) > 180°-(∠SPR + ∠ PSR) ∠SPR + ∠ PSR >∠QPS + ∠ PSQ Since PS bisects ∠P, ∠QPS = ∠SPR ∠SPR + ∠ PSR >∠SPR + ∠ PSQ ∠ PSR >∠ PSQ, Hence proved Q6. Show that of all line segments drawn from a given point not on it, the perpendicular line segment is the shortest.
  • 31. Ans. Let A is an external point out of the line and AC⊥ BC Let BC is a line and AB is a line segment drawn from the point A on the line BC In triangle ΔABC ∠B <∠C (since ∠B is acute angle and ∠C =90° ) AC < AB (side opposite to larger angle is grater) Similarly all line segments drawn from A on the line BC are larger than AC Therefore AC is the shortest side drawn from A on BC, Hence proved NCERT Solutions of Class 9 Science : Chapter 1 to Chapter 15 Class 9-Sample papers and question papers Mid point theorem Solutions of important question papers of last year's question papers Mean,mode median Solutions of specific questions of mensuration How to write linear equation in two variable Technics of achieving hundred percent marks in Maths Maths assignments for class 9 and 10 9 class maths assignment for SA-1 Lines,angles and Triangles Addition, subtraction,multiplication and division of polynomial Number System Class 9 Science NCERT solutions and science notes Chemistry Lesson 1-Matter in our surroundings
  • 32. Chapter 2- Is matter around us pure Chapter 3-Atoms and Molecules Lesson 4-Structure of the Atoms Biology Chapter 5- Fundamental Unit of Life Physics Chapter 8 -Motion Chapter 9 - Force and Laws of Motion Chapter 10- Gravitation Chapter 11-Work and Energy Lesson 12 - Sound Study science notes Archimedes Principle: Complete detail Average Speed and Average velocity Three equation of Motions Recoil velocity of the gun Mole concept The second law of motion The universal law of gravitational force NCERT Solutions Class 10 Science from chapter 1 to 16 NCERT Solutions of all chapters of Maths for Class 10 from Chapters 1 to 15 study NCERT solutions Class 12 Maths Exercise 8.3 -Application of Integrals
  • 33. Exercise 8.1-Application of Integrals Exercise 8.2-Application of Integrals Exercise 7.1- Integrals Exercise 7.2-Integral Exercise 7.3-Integrals Exercise 6.1-Application of Derivatives Exercise 6.2-Application of Derivatives Exercise 6.3 -Application of Derivatives Exercise 6.4- Application of Derivatives Exercise 6.5-Application of Derivations Exercise 5.2 Chapter- Continuity and Differentiability Chapter 5-Continuity and Differentiability Chapter 1- Relations and functions-Download free pdf Class 11 NCERT solutions Chapter 1 of maths, physics and chemistry Chapter 1-Sets(important questions) Chapter 1-Some basic concepts of chemistry Chapter 1- Physical World Chapter 1-Sets- PDF Science and Maths NCERT solutions for Class 9 ,10 and 11 classes exercise 9.1 -Sequence and Series Exercise 9.2- Sequences and Series Important questions of Chapter 1-Sets,
  • 34. NCERT solutions of Chapter 1- Sets NCERT solutions of chapter 5-Complex number NCERT Solutions of chapter 3-Trigonometry Previous year maths question paper of class 11 Maths question paper 2015-16 Maths question paper 2014-15 Maths question paper 2019-20 NCERT Solutions of Class 9 Science : Chapter 1 to Chapter 15 Class 9-Sample papers and question papers Mid point theorem Solutions of important question papers of last year's question papers Mean,mode median Solutions of specific questions of mensuration How to write linear equation in two variable Technics of achieving hundred percent marks in Maths Maths assignments for class 9 and 10 9 class maths assignment for SA-1 Lines,angles and Triangles
  • 35. Addition, subtraction,multiplication and division of polynomial Number System Class 9 Science NCERT solutions and science notes Chemistry Lesson 1-Matter in our surroundings Chapter 2- Is matter around us pure Chapter 3-Atoms and Molecules Lesson 4-Structure of the Atoms Biology Chapter 5- Fundamental Unit of Life Physics Chapter 8 -Motion Chapter 9 - Force and Laws of Motion Chapter 10- Gravitation Chapter 11-Work and Energy Lesson 12 - Sound Study science notes Archimedes Principle: Complete detail Average Speed and Average velocity Three equation of Motions Recoil velocity of the gun Mole concept The second law of motion
  • 36. The universal law of gravitational force NCERT Solutions Class 10 Science from chapter 1 to 16 NCERT Solutions of all chapters of Maths for Class 10 from Chapters 1 to 15 study NCERT solutions Class 12 Maths Exercise 8.3 -Application of Integrals Exercise 8.1-Application of Integrals Exercise 8.2-Application of Integrals Exercise 7.1- Integrals Exercise 7.2-Integral Exercise 7.3-Integrals Exercise 6.1-Application of Derivatives Exercise 6.2-Application of Derivatives Exercise 6.3 -Application of Derivatives Exercise 6.4- Application of Derivatives Exercise 6.5-Application of Derivations Exercise 5.2 Chapter- Continuity and Differentiability Chapter 5-Continuity and Differentiability Chapter 1- Relations and functions-Download free pdf Class 11 NCERT solutions Chapter 1 of maths, physics and chemistry Chapter 1-Sets(important questions) Chapter 1-Some basic concepts of chemistry Chapter 1- Physical World
  • 37. Chapter 1-Sets- PDF Science and Maths NCERT solutions for Class 9 ,10 and 11 classes exercise 9.1 -Sequence and Series Exercise 9.2- Sequences and Series Important questions of Chapter 1-Sets, NCERT solutions of Chapter 1- Sets NCERT solutions of chapter 5-Complex number NCERT Solutions of chapter 3-Trigonometry Previous year maths question paper of class 11 Maths question paper 2015-16 Maths question paper 2014-15 Maths question paper 2019-20 ONLINE SHOPPING WITH A DEAL Top Branded and quality Tee Shirts for men and women in Amazon. Top 10 World Class Branded Shirts for Casual use. 10 Top Word Class Branded Jeans for men at the Discount of 10 – 30 % Top 10 World Class Suit Brands in India :Suitable for attending party,marriage, seminar and conference Get Smart TV of 32, 40 and 43 inch at 50 to 60 % discount The top branded shoes in the market for men The Best updated Camcorders : Camera with video recordings Get Huge Discounts in Laptops Heavy discount on Roll top desktop
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  • 39. Addition, subtraction,multiplication and division of polynomial Number System Class 9 Science NCERT solutions and science notes Chemistry Lesson 1-Matter in our surroundings Chapter 2- Is matter around us pure Chapter 3-Atoms and Molecules Lesson 4-Structure of the Atoms Biology Chapter 5- Fundamental Unit of Life Physics Chapter 8 -Motion Chapter 9 - Force and Laws of Motion Chapter 10- Gravitation Chapter 11-Work and Energy Lesson 12 - Sound Study science notes Archimedes Principle: Complete detail Average Speed and Average velocity Three equation of Motions Recoil velocity of the gun Mole concept The second law of motion
  • 40. The universal law of gravitational force NCERT Solutions Class 10 Science from chapter 1 to 16 NCERT Solutions of all chapters o NCERT Solutions of Class 9 Science : Chapter 1 to Chapter 15 Chapter 1-Number System Chapter 2-Polynomials Class 9-Sample papers and question papers Mid point theorem Solutions of important question papers of last year's question papers Mean,mode median Solutions of specific questions How to write linear equation in two variable Technics of achieving hundred percent marks in Maths Maths assignments for class 9 and 10 9 class maths assignment for SA-1 Lines,angles and Triangles Addition, subtraction,multiplication and division of polynomial Number System Class 9 Science NCERT solutions and science notes Chemistry Lesson 1-Matter in our surroundings
  • 41. Chapter 2- Is matter around us pure Chapter 3-Atoms and Molecules Lesson 4-Structure of the Atoms Biology Chapter 5- Fundamental Unit of Life Physics Chapter 8 -Motion Chapter 9 - Force and Laws of Motion Chapter 10- Gravitation Chapter 11-Work and Energy Lesson 12 - Sound Study science notes