Answer:
D is 117
Step-by-step explanation:
Let the measure of angle C be x
The measure of D is 9 less than twice C
Mathematically that is 2x-9
If both are supplementary, they add up to be 180
Thus;
x + 2x - 9 = 180
3x = 180 + 9
x = 189/3
x = 63
Recall;
D = 2x-9= 2(63) -9 = 126 -9 = 117
