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Explain how to solve a system using substitution, then explain how to solve a system using elimination.
What is: To solve using substitution, write one variable in terms of the other (ie. x=y+5) and substitute this into the second equation. Then solve for the remaining variable (y).
To solve using elimination, add or subtract equations to eliminate one variable. For example, (y-5x=10) + (y+5x=5). Then solve for the remaining variable. So, 2y=15 and y=7.5.