Question

4. The length of a chord of a circle with
radius 10 cm is 16 cm, If OD I AB, then
find the length of OD (O is the centre).​

Answer 1

Answer:

Radius = OA= 10cm

AB is the chord with the length of 16 cm

Draw a perpendicular from the centre of the circle to the chord, bisect the chord .

hence, C is the midpoint of AB .

therefore

AC = AB/ 2= 16/ 2 = 8.

so using pythagoras theorem:

OA² = OC² + AC²

10²= OC² + 8²

100 = OC² + 64

OC² = 100- 64

OC²= 36

OC = 6 .