For the function f(x)=3x^2-8x find:

a. f(2)
= -4

b. f(-3)
= 51

Right?

5 answers

a) 3(2)^2 - 8(2)
= 6^2 - 16
= 36-16
= 20

b) 3(-3)^2-8(-3)
= -9^2 - (-24)
= 81 + 24
= 105
Cyn.. That can't be right. Try it on a calculator..
Watch your order of operation.

a) 3(2)^2 - 8(2)
= 3(4) - 16
= 12 - 16
= -4

Now do b) the same way, the power has to be done first.
Yeah. 51, like I said, right?
Yes, C. , you are right.
I was not paying attention that it was "anonymous" who gave the wrong solution, I thought it was you.

You were right with both answers.