Question

In the following figure, ray PA is a tangent to the circle at A and PBC is a secant. If AP = 15, BP = 10, then find BC.

Answer 1

In the given figure, PA is a tangent segment and PBC is the secant

∴ PB x PC = PA²

`:. 10 xx PC = 15^2`

`:. PC = 225/10 = 22.5`

NOw PB + BC = PC  .............(P - B - C)

∴ 10 + BC = 22.5

∴ BC = 22.5 - 10 = 12.5

 Therefore BC = 12.5