In this video, we are going to look at how to evaluate quadratic functions. Quadratic functions are written in the form $y=ax^2+bx+c$ or $f(x)=ax^2+bx+c$
For example:
When given $y=3x^2+2x-5$ at x=2, we substitute 2 in for where we see x.
$y=3(2)^2+2(2)-5$
Remember to always plug in values in parenthesis (to avoid confusion with signs). Then, this can be simplified to
$y=3(4)+2(2)-5$
and even further to
$y=12+4-5$
to get a final answer of
$y=11$

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