SOLUTION: Solve by the substitution method. x + y = 2 x + y = -9

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Question 243720: Solve by the substitution method.
x + y = 2
x + y = -9
Found 2 solutions by jim_thompson5910, checkley77:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

Start with the given system of equations:


system%28x%2By=2%2Cx%2By=-9%29


x%2By=2 Start with the first equation.


y=2-x Subtract x from both sides.


y=-x%2B2 Rearrange the terms and simplify.


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x%2By=-9 Move onto the second equation.


x-x%2B2=-9 Now plug in y=-x%2B2.


0x%2B2=-9 Combine like terms on the left side.


0x=-9-2 Subtract 2 from both sides.


0x=-11 Combine like terms on the right side.


0=-11 Simplify.


Since this equation is NEVER true for any x value, this means that there are no solutions.


So the system is inconsistent.

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
(x=y) CANNOT = (2 & 9) in the same set of 2 equations.
x + y = 2 or x=2-y
x + y = -9 replace x with (2-y)
2-y+y=-9
2+0=-9
2=9 invalid set of equations.