Answer:
x = 80, y = 100
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 = 7 , then
sum = 180° × 5 = 900°
Sum the interior angles and equate to 900
y + 135 + 140 + 150 + 120 + 135 + 120 = 900, that is
y + 800 = 900 ( subtract 800 from both sides )
y = 100
x and y are adjacent angles and are supplementary, that is sum to 180°
x + y = 180
x + 100 = 180 ( subtract 100 from both sides )
x = 80
Thus x = 80 and y = 100
