if f(x) = 5x + 40, what is f(x) when x = -5?\n-9\n-8\n7\n15

Explanation:

Step1: Substitute x value

Substitute (x = - 5) into (f(x)=5x + 40). (f(-5)=5\times(-5)+40)

Step2: Calculate multiplication

Calculate (5\times(-5)). (5\times(-5)=-25), so (f(-5)=-25 + 40)

Step3: Calculate addition

Calculate (-25+40). (f(-5)=15)

Answer:

D. 15