Determining the midline of a Triangle applying the Midline Theorem.

1. ERICK M. CABUTAJE
Teacher
LOGAC NATIONAL
HIGH SCHOOL

5. ACTIVITY
DIRECTIONS:
1. Draw your own triangle then cut it.
2. Fold your triangle at the center in such a way
that the center line or midline is parallel to one
of its sides or the third side.
3. Cut the triangle at the midline.
4. Shade the smaller triangle.

6. OF A
TRIANGLE

7. MIDLINE THEOREM

8. Complete the following
statements:
 DE = ______
 AD = ______
 AE = ______
1
2
BC
BD
CE

9. Fill in the blanks.
1. If DE = 12, then AC =
2. If AC = 42, then DE =
3. If AD = 7, then AB =
4. If BC = 36, then BE =
5. If BD = 8 and EC = 9, then
BA + CB =
24
21
14
18
34

11. If BE = 12, then GO = 6
FALSE

12. If DE = 13, then
1
2
DG = 13
TRUE

13. 51
If BE = 17, then BE + OG = _____

14. 56
If OB = 15, and GE = 13, then OD +
GD = _____

15. 38
Given: BE = 8
BD = 11
Question: How long is GO + BO?

16. Aling Mids has a triangular farm in their
province. The measures of the sides of
the farm are 9m, 10m and 12m. She
was offered to buy the remaining open
lot adjacent to her farm which extends
to two sides of her farm and doubling
the measures of these two sides. If she
will buy the lot and keep a triangular
farm, can you tell the new perimeter of
her farm using the original sides?
Let’s Find It Out!
9
10
12
P = 18+ 20 + 24 = 62m

18. Solve the following problems:(3 pts each)
1. If LE = 19, then
1
2
LV = ________
2. If BE = 21, then BE + UV = _______
3. If BU = 17, and EV = 14,
then LU + LV = ________
5. If LE = 19, then EV = ________
4. If LU = 56, then
1
2
BL = ________