What does fg(3) equal?

Question

In Algebra 2, I am given the following equation:

 

If f(x) = 1 - x³and g(x) = x + 5, then fg(3) = ?

 

I do not need to show my work. I just need the answer. Do you know how to find the answer to this equation?

Answer 1

fg(3) =

 

f(3)g(3)

 

We are multiplying the two functions.

 

Substitute x = 3 into the functions.

 

(1 - 3³)(3 + 5) =

 

(1 - 27)(8) =

 

-26 * 8 =

 

-208

 

Answer 2

I used a graphing calculator to find the answer, see if this makes sense to you:

 

http://hwmath.net/solutions/fg3.jpg

 

(Updated)