Question

13/20 find the measure of the missing angle. 122° 58° 8° 64°

Explanation:

Step1: Recall angle - sum property

The sum of interior angles of a triangle is 180°.
Let the missing angle be $x$. Then $x + 65^{\circ}+57^{\circ}=180^{\circ}$.

Step2: Solve for the missing angle

$x=180^{\circ}-(65^{\circ} + 57^{\circ})$.
First, calculate $65^{\circ}+57^{\circ}=122^{\circ}$.
Then $x = 180^{\circ}-122^{\circ}=58^{\circ}$.

Answer:

$58^{\circ}$