## Reflection: Writing Across the Disciplines Solving Linear Inequalities: Multiplication and Division - Section 4: Closure

I want to focus on #2 in the student work on this ticket out.  This is a pretty difficult concept to describe and you can see from all the student statements that the idea is still in its infancy.  That said, if we look at stu_work1.tiff we can see that this student understands how the value is changed but that does not show why the inequality would need to change direction.  In stu_work2.tiff the student is basically recalling what they heard in class.  They are not showing much understanding about why the change with the symbol must happen.  Stu_work3.tiff this student is getting closer to understanding the concept of what happens when you multiply or divide by a negative number.  They are making reference to smaller and bigger numbers basically switching, I would tell this student to include an example and they are almost there!  The work in stu_work4.tiff also falls short of the mark.  The student is basically re-writing what is written in the question but not making any reference to why the direction of the symbol had to change.

Writing Across the Disciplines: Writing About Math

# Solving Linear Inequalities: Multiplication and Division

Unit 9: Understanding Equations
Lesson 14 of 15

## Big Idea: This lesson develops the idea of why the inequality symbol is reversed when multiplying or dividing both sides by a negative number.

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Standards:
Subject(s):
Math, Algebra, inequality, coefficient, Commutative, Associative, distributive property, expression, solve linear equalities and inequalities, equation
40 minutes

### James Bialasik

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