With the use the exterior angle theorem to find the measure of each angle. 83

D = 78

C = 35

DEC = 67

Step-by-step explanation:

Using the theorem, angle D and + angle C = 113 degrees.

Then you can set up the equation 10x + 13 = 113. Then you can find x - it's 10.

Then you plug it back in, and angle D = 78 and angle C = 35

Step-by-step explanation:

solve E 1st as its the easiest -

<E + 113deg = 180deg

<E = 180 - 113 = 67deg

by exterior angle theorem, <C + <D = 113deg

so 3y+5 + 7y+8 = 113

10y=100

y=10

<C = 3(10)+5 = 35deg

<D = 7(10)+8 = 78deg

ok then what happened.