In this video, we are going to look at how to evaluate quadratic functions. Quadratic functions are written in the form or . After you finish this lesson, view all of our Algebra 1 lessons and practice problems.

For example:

When given at x=2, we substitute 2 in for where we see *x*.

Remember to always plug in values in parenthesis (to avoid confusion with signs). Then, this can be simplified to

and even further to

to get a final answer of

## Example of Evaluating Quadratic Functions

### Example 1

where

So let’s substitute.

### Example 2

; find

So let’s substitute.

## Video-Lesson Transcript

Let’s go over how to evaluate quadratic functions.

Quadratic functions have this form:

The most important thing to note here is the presence of . This is the highest exponent.

Or this form:

One quadratic function could be

where

So let’s substitute.

Let’s look at another example in a different form.

,

Now, let’s substitute.