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Systems of equations can be solved by graphing or by using substitution or elimination

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Systems of equations can be solved by graphing or by using substitution or elimination. What are the pros and cons of each method? Which method do you like best? Why? What circumstances would cause you to use a different method? Consider some of your responses by indicating pros and cons that you may not have considered or persuading them to see the value of the method you like best (if you chose different methods). Describe situations in which you might use their methods of solving.

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Solution Preview

Solve the system: 2x + y = 9, x - y = 3

Elimination / Addition method

This method is preferred when the coefficients of x terms or y terms in the two equations are equal and have opposite signs. If the coefficients are not already equal and negative, it should be easily possible to render them so by multiplying one or both equations with suitable multiplying factor/s.

We see that the coefficients of y terms in the two equations are equal and have opposite ...

Solution Summary

This solution shows a comparison between the different methods of solving a system of linear simultaneous equations. As an illustration, one problem has been solved by all the methods: Elimination, Substitution and Graphing. A Word file attachment must be opened to view the solution.

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