SOLUTION: Why you are using minus(-)instead of plus(+) in substitution?

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Question 266549: Why you are using minus(-)instead of plus(+) in substitution?
Found 2 solutions by stanbon, Alan3354:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Use minus if it eliminates a variable.
Example:
3x +y = 7
3x -2y = 3
Subtracting will eliminate the x-terms and allow you to solve for "y":
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Use plus if it eliminates a variable.
3x + y = 7
3x - y = 3
Adding will eliminate the y-terms and allow you to solve for "x"
Subtracting would eliminate the x-terms and allow you to solve for "y".
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It's your choice.
Cheers,
Stan H.

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Why you are using minus(-)instead of plus(+) in substitution?
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Who said I did?