SOLUTION: I am homeschooled witht the School of Tomorrow. I am doing Algebra 1, working on the section "Solving Simultaneous Equations Algebraically", the lesson "More About the Substitution

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Question 197681: I am homeschooled witht the School of Tomorrow. I am doing Algebra 1, working on the section "Solving Simultaneous Equations Algebraically", the lesson "More About the Substitution Method." I am having a hard time with problems like this one:
x-y=-1
x-2y=5
I'm very grateful for your help.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
1st) x-y = -1
2nd) x-2y=5
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Solve the 1st Eq. for "x":
x = y -1
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Substitute that into the 2nd equation to solve for "y":
y-1 - 2y = 5
-y = 6
y = -6
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Substitute into x = y -1 to solve for "x":
x = -6 -1
x = -7
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Solution: x = -7 ; y = -6