Question

If XY and X’Y’ are two parallel tangents of a circle with centre O and another tangent AB with point of contact C intersecting XY at A and X’Y’ at B. Then, (a) Prove that AOB = 90º.
(b) If AC = 4 cm and radius of the circle is 3 cm, then find the length of AO​

Answer 1

Answer:

consider the problem

Let us join point O to C

In and ΔOCA

OP=OC (Radii of the same circle)

AP=AC (Tangent from point A)

AO=AO (Common side)

≅ (SSS congruence criterion)

Therefore, P↔C,A↔A,O↔O