To find the measure of the interor angle, we will use the formula:
(n- 2) * 180
where n is the number of sides
In tyhe figure given, the number of polygon sides = 8
substitute n = 8 in the formula and then evaluate
( 8 - 2 ) 180
= 6 * 180
= 1080
But, we were ask to find the measure of each angle
To find the measure of each angle, simply divide the answer by the number of side, which is 8
That is each angle= 1080 / 8 = 135°