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Solving Systems of Equations by Elimination

Solving Systems of Equations by Elimination

Author: Nathan Dingman
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Tutorial

So far in class we have solved systems of equations by graphing and substitution.  The third and final way we have is elimination.  This method is another algebra based method that is useful when the two equations have opposites in them.  Our goal is to eliminate a variable and quickly solve for the other.  

Elimination Example #1

Elimination by simply adding equations together.

Elimination Example #2

Elimination with multiplying to achieve opposites.

Solving Systems of Equations by Elimination Slide Show with Examples