6.4 Elimination by Multiplication.notebook
January 22, 2013
6.4 Elimination Using Multiplication
Sometimes multiplying by ­1 is not enough to make the systems eliminate.
You can multiply one of the equations by numbers other than just ­1.
This allows you to use elimination on any system.
2x ­ y = 4
7x +3y = 27
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6.4 Elimination by Multiplication.notebook
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Sometimes you must multiply both equations. In this case look for a least common multiply.
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6.4 Elimination by Multiplication.notebook
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Elimination by Reordering
Sometimes you may need to change the order of the terms to make the system eliminate.
x=y­3
­y=x+3
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x=­y+1
x+3y=1
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6.4 Elimination by Multiplication.notebook
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2x­2y=2
y­x=­1
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p. 364
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6.4 Elimination by Multiplication.notebook
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Homework:
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6.4 Elimination by Multiplication.notebook
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Workbook Problems:
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6.4 Elimination by Multiplication.notebook
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