Mathematics
ΔABC is an isosceles triangle in which AB = AC, circumscribed about a circle. Prove that the base is bisected by the point of contact.

Answer
We know that,
Tangents from exterior point are equal in length.
We have,
AR = AP, BQ = BP and CQ = CR
Now, AB = AC
⇒ AP + PB = AR + RC
⇒ AR + PB = AR + RC [∵ AR = AP]
⇒ PB = RC
⇒ BQ = CQ.
It means BC is bisected at point Q.
Hence, proved that the base is bisected by the point of contact.
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