Chapter 10, Problem 19RP

To determine

To find : Radius of circle with centre O.

Answer to Problem 19RP

  $\text{r}=20$

Explanation of Solution

Given information :

TP is a tangent segment, TP = $15$ and PQ = $5$

  

Formula Used:

Tangent Secant Theorem : $P{T}^2=PQ\times PS$

Calculation :

Let radius = $\text{r}$

  $\begin{array}{l}\therefore P{T}^2=PQ\times PS\\ \Rightarrow {15}^2=5\times (2\text{r}+5)\\ \Rightarrow \text{r}=20\end{array}$