Question

finding exterior angle measures
find the measure of the exterior angle.
a.
b.

Explanation:

Step1: Use exterior angle theorem (a)

The exterior angle of a triangle equals the sum of the two non-adjacent interior angles.
$x = 36^\circ + 72^\circ$

Step2: Calculate $x$ (a)

$x = 108^\circ$

Step3: Use exterior angle theorem (b)

First find the unknown interior angle: $180^\circ - 60^\circ - 60^\circ = 60^\circ$. The exterior angle equals the sum of the two non-adjacent interior angles.
$2x = 60^\circ + 60^\circ$

Step4: Solve for $x$ (b)

$2x = 120^\circ$
$x = \frac{120^\circ}{2} = 60^\circ$

Answer:

a. $108^\circ$
b. $60^\circ$