Prove that tangents drawn from an external point to a circle are equal. (NCERT Class 10, Circles – Important)

Answer: From external point P, PA and PB touch circle at A,B with center O. OA ⟂ PA and OB ⟂ PB. In right triangles OAP and OBP: OA=OB (radii), OP common, right angles equal. By RHS congruence, PA=PB.