Question

http://prntscr.com/q59t1a

Answer 1

@Hero

Answer 2

So we know that \(m\angle A + m\angle B + m\angle C = 180^{\circ}\)

Answer 3

We also know that since \angles C and \(8x + 15\) are supplementary, \(m\angle C + m\angle(8x+15) = 180^{\circ}\)

Answer 4

So \(C = 180 - 8x + 15\)

Answer 5

That's your hint.

Answer 6

hmm

Answer 7

180-8x+15 is -8x+195

Answer 8

Correct? @Hero

Answer 9

Hang on. It's \(180 - (8x + 15)\)

Answer 10

You still have to solve for \(x\) btw

Answer 11

when I simplify it, it is −8x+165

Answer 12

Okay, so that is your "C"

Answer 13

Now solve for \(x\) by applying \(m\angle A + m\angle B + m\angle C = 180^{\circ}\)

Answer 14

Once you find \(x\), apply it to the expression for \(C\) to find its measure

Answer 15

so (4x+5)+(3x+20)+(-8x+165)=180

Answer 16

x=10

(-8(10)+165) = 85

Answer 17

thats none of the choices

Answer 18

Well, I would recommend you check your work. You know Angles A, B, and C must sum to 180

Answer 19

yes I added them all and equaled it to 180

Answer 20

You may have found C but you're unsure. Use the x you found to find the values of A and B.

Answer 21

Go back to the original question. It says to "Find the value of the EXTERIOR angle

Answer 22

Which means you have to calculate 8x + 15

Answer 23

Sorry I just checked

it is 95

Answer 24

since 8(10)+15=80+15=95

Answer 25

Very good

Answer 26

ty (: making new post one sec