Question

Consider the function f(x) = x2 + 3x − 7. Find the value of f(x) when x = 3 and select the correct answer below.

A. 5
B. 8
C. 11
D. 18

Answer 1

Please help with this, I don't understand

Answer 2

everywhere you see an 'x' replace it with 3 (since x = 3)

\[\Large f(x) = x^2 + 3x - 7\]
\[\Large f(\color{red}{x}) = (\color{red}{x})^2 + 3(\color{red}{x}) - 7\]
\[\Large f(\color{red}{3}) = (\color{red}{3})^2 + 3(\color{red}{3}) - 7\]

Answer 3

now either use pencil/paper or a calculator to evaluate \(\Large (3)^2+3(3)-7\)

Answer 4

Thank you but I still don't know how to evaluate it afterwards, my math is a little rusty

Answer 5

you can use pencil/paper or you can use a calculator

http://web2.0calc.com/

Answer 6

two things to keep in mind

1) type `^` to mean exponent
example: 9 squared = 9^2


2) something like `3(3)` means `3 times 3`. The number next to the parenthesis implies multiplication