(f-g)(x) = x²+6x - (7-x)
(f-g)(x) = x² + 6x - 7 + x
(f-g)(x) = x² + 7x - 7
(f-g)(9) = 9² + 7*9 - 7
(f-g)(9) = 81 + 63 - 7
(f-g)(9) = 137
Answer:
x = 47
Step-by-step explanation:
Every triangle's interior angles add up to 180°.
Let's make an equation.
x + 102 + 31 = 180
x + 133 = 180
x = 47