Question

In a triangle ABC , if angle A +angle B = 108 degree ,angle B +angle C =130 degree find angle A , angle B , and angle C .

Answer 1

∠A+∠B=108° → equation 1
∠B+∠C=130° → equation 2
Adding equation 1 and 2 we get,
∠A+2∠B+∠C=238° → equation 3
and we know that : ∠A+∠B+∠C=180° → equation 4
∴ Subtracting equation 4 from 3 we get;
∠B=58°
∴∠A=50°  (from equation 1)
 and ∠C=72° (from equation 2)

∴ ∠A=50°,∠B=58°,∠C=72°

Answer 2

Pic have the solution