Watch Out for Those Curves!

Contributor: Jamie Hagler. Lesson ID: 13794

Have you ever tried to hit a curveball? Math can throw curves at you too. Check out this lesson and learn all about parabolas!


Algebra I

learning style
personality style
Golden Retriever
Grade Level
High School (9-12)
Lesson Type
Skill Sharpener

Lesson Plan - Get It!

  • We see lines everywhere in math, but what about arches and curves?
  • What happens when information increases and then decreases?
  • What about when it decreases and then increases?

Curves are everywhere in math -- we just need to look for them!

A parabola is a U-shaped graph that opens up or down. The equation, which forms a parabola, is called a quadratic function and is in the form y = ax2 + bx+ c.


Graphing a parabola can be challenging, but here is a sure-fire way to get it done!

Let's look at the quadratic function y = x2 - 2x - 3.

Substitute the x values listed below into this quadratic function to determine the corresponding y values:

x values

Here is what it looks like as we substitute each x into the function. Notice when we substitute the first x, which is -1, we will get 0. So, the first point is (-1,0). Then we repeat for each remaining x.


Now, we need to plot each of those points on the graph. As you see, instead of a line, we have a curve called a parabola!

parabola graph

  • What would make the parabola open in the opposite direction?

Let's go to the Got It? section to find out!

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