Respuesta :

LammettHash

Angles ABC and CBD are complementary - they add up to 90°. This means

(4x + 52°) + (8x - 10°) = 90°

Solve for x :

12x + 42° = 90°

12x = 48°

x = 4°

It follows that angle CBD has measure

4 • 4° + 52° = 16° + 52° = 68°