xChapter 3 & 4 Day #1 ­ Solving by Rewriting (3.1.3) Notes.notebook
September 19, 2016
Chapter 3 & 4 Day #1
Solving by Rewriting
(Section 3.1.3)
Objectives:
Students will.....
1. Rewrite and solve equations and systems of equations, sometimes using substitution.
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xChapter 3 & 4 Day #1 ­ Solving by Rewriting (3.1.3) Notes.notebook
September 19, 2016
In the past few lessons, you have worked recognizing and finding equivalent expressions. In this lesson, you will apply these ideas to solve equations. Grace was trying to solve the quadratic equation, “I think I need to use the quadratic formula because of the decimals.” Walter replied “I’m sure there’s another way! Can’t we rewrite this equation so there aren’t any decimals?”
a. What is Walter talking about? Rewrite the equation so it has no decimals. b. Solve the problem.
SOLVING by REWRITING
Rewriting the equation in the problem above gave you a new, equivalent equation that was much easier to solve. With your team, find an equivalent equation or system that you think might be easier to solve. Then solve your equation.
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xChapter 3 & 4 Day #1 ­ Solving by Rewriting (3.1.3) Notes.notebook
September 19, 2016
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xChapter 3 & 4 Day #1 ­ Solving by Rewriting (3.1.3) Notes.notebook
September 19, 2016
MORE EQUIVALENT EQUATIONS
Rewrite each of the following in another form by solving for y. Rewrite the equations above by solving for x.
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xChapter 3 & 4 Day #1 ­ Solving by Rewriting (3.1.3) Notes.notebook
September 19, 2016
None of the equations below are equivalent. Show that this is true by rewriting the equations.
Angela and Dominic were working on finding roots of two quadratic equations: and
Angela made an interesting claim: “Look. When I solve each of them for , I get the same solutions.
So these equations must be equivalent!” Dominic is not so sure. “How can they be equivalent if one of the equations has a factor of 2 that the other equation doesn’t?”
a. Who is correct? Are the two equations equivalent? How can you justify your answer?
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xChapter 3 & 4 Day #1 ­ Solving by Rewriting (3.1.3) Notes.notebook
September 19, 2016
b. Are the solutions to and
equivalent solutions? How can you justify your answer?
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