Answer:
x = 100 , x = 3
Step-by-step explanation:
(a)
the sum of the interior angles of a polygon is
sum = 180° (n - 2) ← n is the number of sides
here n = 5 , then
sum = 180° × 3 = 540°
sum the angles and equate to 540
x + x + 125 + 125 + 90 = 540 , that is
2x + 340 = 540 ( subtract 340 from both sides )
2x = 200 ( divide both sides by 2 )
x = 100
(b)
the 2 given angles are alternate exterior angles and are congruent , then
6x + 18 = 2x + 30 ( subtract 2x from both sides )
4x + 18 = 30 ( subtract 18 from both sides )
4x = 12 ( divide both sides by 4 )
x = 3