1. 8 Chapter CIRCLE III

8. 8.1 (a) Identify Tangents

9. P A Q Circle Straight Line Intersection at point A What is tangent ?

10. When a circle and a straight line intersect at 1 point, we called that line as a tangent .

11. P A Q Tangent to a circle

12. Is this a tangent ? Tangent to a circle A B C

13. Is this a tangent ? Tangent to a circle X Y Z

14. Which are tangents to a circle ? A C D F E O H B G Answer : Tangent CD at point A Tangent GH at point B

15. Which are tangents to a circle ? Answer : Tangent AB at point H Tangent AC at point E A E D C B H F G Tangent BD at point G

16. Hiii… Everyone, are you ready to learn the next lesson.. ?

17. Next concept

18. Tangent to a circle is perpendicular to the radius of the circle that passes through the contact point .

19. P Q Tangent to a circle Radius 90 0 = perpendicular

20. P O R Q Tangent PQ perpendicular with radius OP. Tangent RQ perpendicular with radius OR.

21. 8.1 (b) Construct the tangent to a circle passing through a point : a) on the circumference of the circle b) outside the circle

24. The Properties Related To Two Tangents From A Given Point Outside The Circle 8.1c

25. What is The Properties Related To Two Tangents From A Given Point Outside The Circle? Let’s do this activity together

26. 1. Use the previous figure and construct segment from centre to the contact point on the circumference of the circle.

27. 2. Using a ruler and a protractor, measure and record the lengths and angles in table. Value Angle Length

29. 3. are congruent.

30. SUMMARY A tangent to a circle is ____________ to the radius drawn through the _________ A tangent to a circle is a __________ ____________________________ O A c O B C AB and AC are _______ to the ________ AC BC OBC and OAC are ___________

31. SUMMARY A tangent to a circle is perpendicular to the radius drawn through the contact point . A tangent to a circle is a straight line which touches the circle at a point. A c O B C AB and AC are tangents to the circle . AC = BC OBC and OAC are congruent . O