tolong jawab nomor 5 ya

Bab Garis dan Sudut

∠A = 2/3 ∠B

a. ∠A + ∠B = 90°
2/3 ∠B + ∠B = 90
5/3 ∠B = 90
∠B = 90 × 3/5
∠B = 54°

∠A
= 90 - ∠B
= 90 - 54
= 36°

b. ∠A + ∠B = 180°
2/3 ∠B + ∠B = 180
5/3 ∠B = 180
∠B = 180 × 3/5
∠B = 108°

∠A
= 180 - ∠B
= 180 - 108
= 72°