If perpendiculars from any point within an angle on its arms are congruent, prove tht it lies on the bisector of that angle.
Given: A point P lies in the angle ABC and PL⊥ BA and PM⊥ BC and PL=PM. PB is joined
To prove : PB is the bisector ∠ABC,
Proof : In right ΔPLB and ΔPMB
Side PL = PM (Given)
Hyp. PB = PB (Common)
∴ ΔPLB≅ ΔPMB (RHS axiom)
∴ ΔPBL=ΔPBM (c.p.c.t.)
∴ PB is the bisector of ∠ABC