Things to remember the sum of the measures of the interior and exterior angles at each vertex is 180 (supplementary angles)
add and equal to 180
3x-5+5x+17= 180
8x+12=180
8x= 168
x=21
substitute in the algebraic expression for exterior angle
3(21) -5=
63-5=58
58 degrees is the exterior angle
hope this helps
18.00 + 8.50 + 8.50 + 8.50 + 8.50 = 52.00
So that's 4 Friends
