## Reflection: Developing a Conceptual Understanding Solving Equations - Section 1: Bell work

When I explain why we may get a false solution I work with students to see how doing some algebraic techniques can change the function. This resource shows a little of what I do with example 2 from the bell work.  We begin by looking at the 2 sides of the equation on different graphs. The class will rewrite the original equation by multiplying by the common denominator so the students get 2=(x-2)+(x-4). I graph each side again to show how the graphs of each side of the equation has changed. Next I overlay one graph onto the other side (this can be challenging but using transparency tools it is possible) I line up the axes and then show how the new equation intersect while the original equation do not intersect.

Seeing ideas visually helps student develop the understanding needed to realize why we get extraneous solutions.

Developing a Conceptual Understanding: Explaining extraneous solutions

# Solving Equations

Unit 10: Solving Equations
Lesson 1 of 6

## Big Idea: Students are reminded of the power of algebra as a general problem solving tool.

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Standards:
Subject(s):
Math, solving equations, Applications of equations
55 minutes

### Katharine Sparks

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