Question

find the measure of the missing angle.

Explanation:

Step1: Recall the property of a straight angle

A straight angle measures \(180^{\circ}\).

Step2: Set up the equation

Let the missing angle be \(a\). We know that \(a + 39^{\circ}=180^{\circ}\).

Step3: Solve for \(a\)

Subtract \(39^{\circ}\) from both sides of the equation: \(a=180^{\circ}- 39^{\circ}\).

$$a = 141^{\circ}$$

Answer:

\(141^{\circ}\)