Answer:
∠A = 73°
Step-by-step explanation:
The sum of the interior angles in a polygon is
sum = 180° (n - 2) ← n is the number of sides
Here n = 5 since polygon shown has 5 sides, thus
sum = 180° × 3 = 540°
let x be the measure of the fifth angle in the polygon, then
104 + 118 + 96 + 115 + x = 540, that is
433 + x = 540 ( subtract 433 from both sides )
x = 107
The angles x and A form a straight angle and are supplementary, thus
∠A + x = 180, that is
∠A + 107 = 180 ( subtract 107 from both sides )
∠A = 73°
