In this lesson, students write an equation for a parabola and rewrite it in vertex form. Then, they match graphs of parabolas to equations. Students reason abstractly and quantitatively (MP2) as they create a parabola equation by applying the concept of distance calculations.
Lesson overview
 8.1 Warmup: Focus on Distance (5 minutes)
 8.2 Activity: Building an Equation for a Parabola (20 minutes)

8.3 Activity: Card Sort: Parabolas (10 minutes)
 Includes "Are you Ready for More?" extension problem
 Lesson Synthesis
 8.4 Cooldown: One More Equation (5 minutes)
Learning goals:
 Generalize (using words and other representations) the process of repeated distance calculations to derive an equation for a parabola in the coordinate plane.
Learning goals (student facing):
 Let’s write an equation for a parabola.
Learning targets (student facing):
 I can derive an equation for a parabola in the coordinate plane given a focus and a directrix.
Required materials:
 Graphing technology
 Preprinted slips, cut from copies of the blackline master
Required preparation:
 The graphing technology is for use in the extension problem of the activity Card Sort: Parabolas.
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