SOLUTION: I don't know where to begin on a problem here. Can someone help me out? Evaluate g(x) = x^2 + 4x for a. g(2) b. g(-2) Thank you!

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: I don't know where to begin on a problem here. Can someone help me out? Evaluate g(x) = x^2 + 4x for a. g(2) b. g(-2) Thank you!      Log On


   

Question 26265: I don't know where to begin on a problem here. Can someone help me out?
Evaluate g(x) = x^2 + 4x for
a. g(2)
b. g(-2)
Thank you!
Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
Functions are truly easy things to use...

Given g(x) = x%5E2+%2B+4x

this says... given the "number" x in the g(x) definition, we alter it as defined by x%5E2+%2B+4x.

So, g(2) is %282%29%5E2+%2B+4%282%29
--> g(2) is 4 + 8
--> g(2) = 12

and g(-2) is %28-2%29%5E2+%2B+4%28-2%29
--> g(-2) = 4 - 8
--> g(-2) = -4

Can you see how simple it is?

jon.