## Reflection: Grappling with Complexity Solving Systems Using Elimination: An Intuitive Approach -- Day 2 of 2 - Section 2: Investigation

Many of my students have taken some algebra before and may have seen the elimination method before. Though I love the intuitive approach this series of tasks takes, I do find students get confused about whether or not they are adding the two equations together or subtracting them. This is a great opportunity to talk about what the difference is (adding versus adding negative numbers to make them cancel out or subtracting).  Ultimately, I try to have students focus on what they need to do get a variable to cancel itself out in both equations. Also, students need to be reminded that if they change the sign of one variable, they need to do that throughout the rest of the equation.

Grappling with Complexity: Adding or subtracting the equations?

# Solving Systems Using Elimination: An Intuitive Approach -- Day 2 of 2

Unit 3: Systems of Equations and Inequalities
Lesson 8 of 17

## Big Idea: Where is the difference in price? Students reasons through receipts in order to see the structure of solving systems using elimination.

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Standards:
Subject(s):
Math, Algebra, Systems of Equations and Inequalities, systems of equations, solving systems of equations using elimination
60 minutes

### Amanda Hathaway

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