Find the measure of angle C and angle D. show your work.

C=40 degrees D=76 degrees

Step-by-step explanation:

Because of a theorem angle c and d equal angle DEF

so here is our equation:4y+(7y+6)=116

Open the parentheses

4y+7y+6=116

-6 on both sides

4y+7y=110

11y=110

Divide both sides by 11

y=10

Now we have to substitute

C=4y=4(10)=40

D=7y+6=7(10)+6=70+6=76

the sum of all the angles in a triangle are equal to 180

so you can add   the 3 given angles together to equal 180:

5y + 2y + 2y = 180

or since all three angles have the same letter, combine the 3 angles to equal 180:

9y = 180