Answer:
y = 32; x = 59
Step-by-step explanation:
On the top triangle x+y+89=180 because a triangle's angles add up to 180 degrees, while a quadrilateral's angles add up to 360 degrees.
Angle 89 and the angle below it are supplementary, meaning together they equal 180 degrees.
180 - 89 = 91
So the angle below 89 is 81 degrees.
Now we can subtract the other three angles in the quadrilateral to find the fourth:
360 - (78 + 43 + 91) = 148
So the angle below y is 148 degrees.
Angle y and the angle below it are supplementary, meaning together they equal 180 degrees.
y = 180 - 148
y = 32
All of the angles in a triangle equal 180 degrees:
x = 180 - (32 + 89)
x = 59
