Answer:
Step-by-step explanation:
x^2 + 2x = 6x+45
x^2 -4x -45 =0
x^2 - 5x +9x -45 =0
x(x-5) +9 (x-5)=0
(x-5)(x+9)=0
x = 5, -9
x = 5; measure of exterior angle = 5^2+2(5) = 35
x=-9; measure of exterior angle = (-9)^2 + 2(-9) = 63
