Answer:
x = 30
Step-by-step explanation:
The sum of the interior angles of a polygon is
sum = 180° (n - 2) ← n is the number of sides
Here n = 5, thus
sum = 180° × 3 = 540°
Sum the given angles and equate to 540, that is
x + 106 + 90 + 74 + 8x = 540, simplify
9x + 270 = 540 ( subtract 270 from both sides )
9x = 270 ( divide both sides by 9 )
x = 30
