Question

Please help thank you.

Answer 1

Because they are same-side interior they are supplementary:

5x + 15 + 3x - 3 = 180
8x + 12 = 180
x = 21

5x + 15 = a
5(21) + 15 = a
120 = a

Hope this helps!

Answer 2

x=21 angle 1 equals 120

to find x you make am equation of 5x+15+3x-3=180 8x+12=180 x=21. then plug in 21 for x 5(21)+15 gives you the angle of 1 because Angel 1 and (5x+15) are corresponding angels in which they well have the same measurement