Lesson Materials

Lesson 6-3: Ellipses

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The student will be able to define an ellipse, graph an ellipse, locate its center, endpoints and foci.

Drag the point P and it observe the figure formed.

1. What represent the segments green and purple?

Move sliders a and c.

2. What is the relationship between a and c. When their values are close together? When their values are far apart? When their values are the same?

3. What is the equation of the ellipse of the figure?

4. Moves point Q and it observe what happens to the equation. When does point Q satisfy the equation of the ellipse? Outside the ellipse? Inside the ellipse? on the ellipse?

  1. Click the Play Button under the movie.

  2. The two blue segments change in length, but their sum remains constant.

  3. The trail of red dots forms an ellipse.

Livemath: An interactive website that explains the parts and properties of ellipses. Livemath

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