## Reflection: Connection to Prior Knowledge Exploring Ellipses - Section 2: Explore

My students had a pretty easy time with ellipses since they studied them in depth in Algebra 2, but they did have considerable difficulty with the process of completing the square when the coefficient of the squared term is not 1. Here you can see what happened for many students - they could complete the square for the x-terms but not for the y-terms.

When we had our whole class discussion, we had to have a quick discussion about factoring out the 4, and then making sure we added the correct number to the right side of the equation (since the constant must be multiplied by 4 too).

Connection to Prior Knowledge: Completing the Square

# Exploring Ellipses

Unit 10: Conic Sections
Lesson 2 of 10

## Big Idea: Define an ellipse in three different ways.

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1 teacher likes this lesson
Standards:
Subject(s):
Math, Precalculus and Calculus, ellipse, eccentricity, conic sections
50 minutes

### Tim Marley

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