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Evaluating Quadratic Functions

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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