Answer:
x = 18
y = 15
Step-by-step explanation:
Remark
Step One
The main step is to realize that if the lower left hand angle is 90 degrees, then the upper left hand angle is also 90. That is because the interior angles of parallel lines are supplementary. If one of the angle is 90 degrees, so is the other.
Conclusion from the Remark
5x = 90
x = 90/5
x = 18 degrees
Step Two
Find y
y is just a bit harder to find . The safest way is to add all four interior angles together. For any trap*zoid (you cannot spell this word properly. The editor has a fit), the interior angles add up to 360 degrees.
So just add the 4 angles together and equate to 360
5(y + 11) + 4y - 10 + 90 + 90 = 360 Combine like terms
5(y + 11) + 4y - 10 + 180 = 360 Combine again
5(y + 11) + 4y + 170 = 360 Subtract 170 from both sides
5(y + 11) + 4y = 360 - 170 Combine like terms
5(y + 11) + 4y = 190 Remove the brackets
5y + 55 + y4 = 190 Combine like terms
9y + 55 = 190 Subtract 55 from both sides.
9y = 190 - 55
9y = 135 Divide by 9
y = 135 / 9
y = 15
