Question

In a ∆ABC, if ∠A = 55°, ∠B = 40°, find ∠C.

Answer 1

Required angle= 180-(angleA+angleB)
=180-95
=85°

Answer 2

Given :

ABC is a Δle.

∠A = 55°

∠B = 40°

∠C = x °

∠A + ∠B+ ∠C = 180° ↔ Angle sum property of a Δle.

55 + 40 + x = 180

95+x = 180

∴ x = ∠C = 180-95

= 85°