Question

find the measure of the missing angle.

Explanation:

Step1: Recall angle - sum property

The sum of adjacent angles forming a straight - line is 180°.

Step2: Set up the equation

Let the missing angle be \(a\). We have \(a + 100^{\circ}=180^{\circ}\).

Step3: Solve for \(a\)

Subtract 100° from both sides of the equation: \(a=180^{\circ}- 100^{\circ}\).

Answer:

\(80^{\circ}\)