What is the length of ST?

enter image source here

1 Answer
Jun 5, 2018

ST=sqrt210 ~~14.49 inches

Explanation:

By tangent-secant theorem , we have

"(T angent)"^2="(Whole Secant)"xx"(External Secant)"

i.e. TS^2=TQxxTR

Tangent =TS

Whole Secant =TQ==TR+RQ=7+23=30 inches

External Secant =TR=7 inches

rarrST^2=RTxxQT

toST=sqrt(RTxxQT

rarrST=sqrt(7xx30)=sqrt(210)~~14.49 inches