SOLUTION: how do you solve a linear system by graphing the problem is x+y=-2 -x+y=6 please help thank you

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Question 460992: how do you solve a linear system by graphing the problem is
x+y=-2
-x+y=6
please help thank you
Found 2 solutions by MathLover1, stanbon:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

x%2By=-2+
-x%2By=6+

Solved by pluggable solver: Solve the System of Equations by Graphing



Start with the given system of equations:


1x%2By=-2

-x%2By=6





In order to graph these equations, we need to solve for y for each equation.




So let's solve for y on the first equation


1x%2By=-2 Start with the given equation



1y=-2-x Subtract +x from both sides



1y=-x-2 Rearrange the equation



y=%28-x-2%29%2F%281%29 Divide both sides by 1



y=%28-1%2F1%29x%2B%28-2%29%2F%281%29 Break up the fraction



y=-x-2 Reduce



Now lets graph y=-x-2 (note: if you need help with graphing, check out this solver)



+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+-x-2%29+ Graph of y=-x-2




So let's solve for y on the second equation


-x%2By=6 Start with the given equation



1y=6%2Bx Add +x to both sides



1y=%2Bx%2B6 Rearrange the equation



y=%28%2Bx%2B6%29%2F%281%29 Divide both sides by 1



y=%28%2B1%2F1%29x%2B%286%29%2F%281%29 Break up the fraction



y=x%2B6 Reduce





Now lets add the graph of y=x%2B6 to our first plot to get:


+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+-x-2%2Cx%2B6%29+ Graph of y=-x-2(red) and y=x%2B6(green)


From the graph, we can see that the two lines intersect at the point (-4,2) (note: you might have to adjust the window to see the intersection)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
how do you solve a linear system by graphing the problem is
x+y=-2
-x+y=6
----
Solve for "y":
y = -x-2
y = x+6
-----
Graph them both on the same coordinate axes:
graph%28400%2C300%2C-10%2C10%2C-10%2C10%2C-x-2%2Cx%2B6%29
===============================================
Cheers,
Stan H.
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