Question

find the measure of the missing angle.

Explanation:

Step1: Recall angle - addition property

The two angles form a straight - line, and the sum of angles on a straight - line is 180°. So, $a + 29^{\circ}=180^{\circ}$.

Step2: Solve for the unknown angle

Subtract 29° from both sides of the equation: $a=180^{\circ}- 29^{\circ}$.
$a = 151^{\circ}$

Answer:

$151^{\circ}$