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Solve the system using elimination and describe your steps. Be sure to verify your solution. • x = y - 3 2x + y = 12

User Ppearcy
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1 Answer

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So these are our two equations:
2x+y=12\\x=y-3

Before we can use elimination, subtract y on both sides of the first equation:
2x=-y+12\\x=y-3

Now we are able to use elimination. To eliminate the y variable, add the two equations together to get
3x=9 . From here we can solve for x.

For this, just divide both sides by 3 and your first answer will be
x=3

Now that we have the value of x, substitute it into either equation to solve for y:


2*3+y=12\\6+y=12\\y=6\\\\3=y-3\\6=y

In short, x = 3 and y = 6.

User Sen Jacob
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