Question

In following fig., PT is a tangent to the circle at T and PAB is a secant to the same circle. If PA = 4cm and AB = Scm, find PT.

Answer 1

Let PT = x cm 

Since, PAB is a secant and PT is a tangent to the given circle, we have, 

PA · PB = PT² 

⇒  4 · 9 = PT² 

⇒ PT² = 36 

⇒ PT = 6cm