Answer: <C = 32, <D = 80, <DEC = 68
Explanation:
First, the exterior angle DEF equals the sum of the two other interior angles that are not adjacent to it, meaning that the angle DEF equals the sum of angles DCE and EDC.
Therefore, you get the equation
2y+8+6y+8=112
8y+16=112
8y = 96
y = 12
Since y is 12, let's use this to find the measure of the other angles.
DCE = 2y+8 = 32
EDC = 6y+8 = 80
Angle DEC equals 180 - 112 = 68