Question

Given f(x) = x^2- 3x + 5, what is f(-2)?

Answer 1

Step-by-step explanation:

f(x) = x² - 3x + 5

f(-2) = (-2)² - 3.(-2) + 5

f(-2) = 4 + 6 + 5

f(-2) = 15

Answer 2

Answer:

Step-by-step explanation:

Comment

In general, f(x) can be thought of as being y. So the equation could read as "Let x = - 2" when y = x^2 - 3x + 5.

Another way of thinking of it is by saying f(-2), wherever you see an x on the right hand side, substitute the value given on the left side (in this case x = - 2

Solution

f(-2) = (-2)^2 - 3x + 5

f(-2) = 4 - 3(-2) + 5                   Combine

f(-2) = 4 + 6 + 5                        Add

f(-2) = 15