In a triangle ABC, if ∠A + ∠C = 140° and ∠A + 3∠B = 180°, then ∠A is equal to:

A. 80°

B. 40°

C. 60°

D. 20°

Answer: Option C

Solution(By Examveda Team)

∠A + ∠B + ∠C = 180°
            (for a triangle)
∠A + ∠C = 140°
then, ∠B = 40°
∠A + 3∠B = 180°
∠A + 120° = 180°
⇒ ∠A = 60°