Question

If f(x)= x^2-2x and g(x)= 6x+4 for which value of x does (f+g)(x)=0

Answer 1

x = - 2

Explanation:

(f + g)(x) = f(x) + g(x)

f(x) + g(x) = x² - 2x + 6x + 4 = x² + 4x + 4 ← equating to 0

x² + 4x + 4 = 0 ← in standard form

(x + 2)² = 0 ← in factored form, thus

x + 2 = 0 ⇒ x = - 2