16. Find the value of y.
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y + (2x -12) = 180 (since they are supplementary angles)
(2x-12) = 96 ( since they are alternate exterior angle)
2x = 96 + 12
2x = 108
x = 108/2
x = 54.
y+( 2x-12)=180
y+(2× 54 -12) = 180
y + (108-12) = 180
y + 96 = 180
y= 180-96
y = 84.