Two angles are said to be complementary if the some of those two angles is equal to 90°
Given : ∠WXY and ∠YXZ are complementary angles
⇒ ∠WXY + ∠YXZ = 90°
Given : ∠WXY = (2x + 5)° and ∠YXZ = (8x - 5)°
⇒ (2x + 5)° + (8x - 5)° = 90°
⇒ 10x = 90°
⇒ x = 9°
Substituting the value x = 9° in angles ∠WXY and ∠YXZ, we get :
⇒ ∠WXY = 2(9) + 5 = 18 + 5 = 23°
⇒ ∠YXZ = 90° - 23° = 67°