Question

∠a and ∠b are complementary angles ∠a measures 78° What is the measure of ∠b?

Answer 1

Good evening ,

Answer:

∠b = 12°

Step-by-step explanation:

∠a and ∠b are complementary angles ⇔ ∠a + ∠b = 90

Then ∠a =90 - ∠b = 90 - 78 = 12°

:)