Two angles, ∠1 and ∠2 , in a diagram are supplementary. If m∠1=77°, what equation can you write to solve for m∠2? Let m∠2=x°

Question

O x + 77° = 90°
O x = 77°
O x + 77° = 180°
O x = 90° - 77°

Answer 1

The equation that can be written to solve for m∠2 is:

x + 77° = 180°