Find the value of x by using the exterior angle theorem.

The first choice (12)

Step-by-step explanation:

i'm not 100% what the theory is but here is how I did it:

the angle D and 115% are supplementary which means they add up to 180.

115+x=180

x=65

so now that you know all the angle measures, you also know that all angles of a triangle add up to 180.

65+3x+19+5x=180

combine like terms:

8x+84=180

subtract 84 from both sides:

8x=96

divide by 8 on both sides

x=12

well there are two answers for that.

1: you need 120 ones then that will equal up to 120.

2: you could also do one 100 and 2 tens.

those are the answers that i have thought of.

step-by-step explanation:

what is the figure? attach a picture.