J P Mohindru and Bharat Mohindru Solutions for Chapter: Circles, Exercise 1: EXERCISE

If the tangent at a point $P$ to a circle with centre $O$ cuts a line through $O$ at $Q$ such that $PQ=24 \mathrm{cm}$ and $OQ=25 \mathrm{cm}$. Find the radius of the circle.

$O$ is the centre of a circle of radius $8 \mathrm{cm}$. The tangent at a point $A$ on the circle cuts a line through $O$ at $B$ such that $AB=15 \mathrm{cm}$. If $OB=x \mathrm{cm}$, then find the value of $x$.

$PQ$ and $PT$ are tangents to a circle with centre $O$ and radius $5 \mathrm{cm}$. If $PQ=12 \mathrm{cm}$, then prove that the perimeter of the quadrilateral $PQOT$ is $34 \mathrm{cm}$.