Question 620217
Hi, there--
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Use the Substitution method to solve this system of equations: 
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{{{x=-y-1}}}
{{{x-y=-11}}}
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Substitute -y-1 for x in the second equation. (We can make this move because the first equation tells us that whatever x is, it is equal to -y-1.)
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{{{x-y=-11}}}
{{{(-y-1)-y=-11}}}
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Simplify by combining like terms.
{{{-2y-1=-11}}}
{{{-2y=-10}}}
{{{y=5}}}
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Substitute 5 for y in the first equation.
{{{x=-y-1}}}
{{{x=-(5)-1}}}
{{{x=-6}}}
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According to our algebra, x=-6 and y=5. Thus the ordered pair (-6,5) is the solution to this system of equations. If you graphed these equations you would see two lines intersecting at (-6,5).
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Last step, check the solution in both equations. (It's very east to make an error.)
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x=-y-1 
(-6)=-(5)-1
-6=-6 
Check!
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x-y=-11
(-6)-(5)=-11
-11=-11
Check!
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Feel free to email me  if you still have questions about this.
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Ms.Figgy
math.in.the.vortex@gmail.com