Question

If f(x) = 4x - 3 and g(x) = x + 4, find (f-g)(x).

A. 3x-7
B. 5x-1
C. 5x - 7
D. 7 - 3x

Answer 1

9514 1404 393

Answer:

A. 3x -7

Explanation:

Substitute for f and g, then collect terms.

(f -g)(x) = f(x) -g(x) = (4x -3) -(x +4)

(f -g)(x) = 4x -3 -x -4 = (4-1)x +(-3-4)

(f -g)(x) = 3x -7