# Write a Function in Slope-Intercept Form

## Key Questions

• Assuming your function is expressed using $x$ as a variable, evaluation of the function involves replacing each occurrence of $x$ with some per-specified value.

That is evaluation of a function is always "at some point#.

For example if your function is
$f \left(x\right) = 3 {x}^{2} - x + 4$
and you are asked to evaluate this function at $x = 2$

$f \left(2\right) = 3 \left({2}^{2}\right) - 2 + 4 = 14$

(Since this question was asked under "Functions in Slope-Intercept Form, your function might look more like:
$y = 5 x + 7$
and you might be asked to "evaluate $y$ at $2$", but the same idea applies:
$y = 5 \left(2\right) + 7 = 17$ )