Question

On section 3.2 Homework, Question 9, how can you tell what f(-3) equals? Do you just plug -3 into all of the x variables in the equation?

Answer 1

Yes, we need to plug in -3 into f(x) to find f(-3).

We need to substitute x = -3 in f(x) to get f(-3)

Put -3 in place of variable x in f(x).

For example, we have f(x) = 2x+7

For f(-3), put x = -3 in f(x)

f(-3) = 2(-3)+7

= -6+7

= 1

We need to just plug -3 into all of the x variables in the equation.