Question

If f(x) = 10x + 7 and g(x) = x^2 - 7x, find (f - g)(x)

A. (f - g)(x) = x^2 + 3x + 7
B. (f - g)(x) = 10x^3 - 63x^2 - 49x
C. (f - g)(x) = -x^2 + 17x + 7
D. (f - g)(x) = 10x + 7

Answer 1

C

Explanation:

note that (f - g)(x) = f(x) - g(x)

f(x) - g(x)

= 10x + 7 - (x² - 7x) ← distribute parenthesis by - 1

= 10x + 7 - x² + 7x ← collect like terms

= - x² + 17x + 7 → C