Question

I need help solving this problem.

Answer 1

The answer I got is x^3 + 14x - 9x

Answer 2

(f+g-k)(x) means to add the equations f(x) and g(x) then subtract k(x)

2x^2 + 3x + 4x - 9 = 2x^2 +7x -9

2x^2 + 7x - 9 - x^2 -7x = x^2 -9

The answer is : x^2 - 9