Question

find missing angles quick check
two angles ∠1 and ∠2 in a diagram are supplementary. if m∠1 = 77°, what equation can you write to solve for m∠2 = x? (1 point)
options:

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

Explanation:

Step1: Recall supplementary angles rule

Supplementary angles sum to $180^\circ$.

Step2: Set up the equation

Let $m\angle2 = x^\circ$, so $x^\circ + 77^\circ = 180^\circ$.

Answer:

$\boldsymbol{x^\circ + 77^\circ = 180^\circ}$ (corresponding to the option: $x^\circ + 77^\circ = 180^\circ$)