Given: O and C are the centre of Two circles touching each other externally at P. PT is its common tangent
From a point T: PT, TR and TQ are the tangents drawn to the circles.
Required to prove: TQ = TR
Proof:
$TR$ and $TP$ are two tangents to the circle with centre $O$ , From $T$
So, $TR=TP$ ….(i)
Similarly, from point $T$
$TQ$ and $TP$ are two tangents to the circle having centre $C$
$TQ=TP$ ….(ii)
From (i) and (ii) ⇒
$TQ=TR$
– Hence proved.