SOLUTION: solve by graphing x-y=1 x+y=-1

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Question 172813: solve by graphing
x-y=1
x+y=-1
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-y=1%2Cx%2By=-1%29


In order to graph these equations, we must solve for y first.


Let's graph the first equation:


x-y=1 Start with the first equation.


-y=1-x Subtract x from both sides.


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


y=x-1 Rearrange the terms and simplify.


Now let's graph the equation:


Graph of y=x-1.


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Now let's graph the second equation:


x%2By=-1 Start with the second equation.


y=-1-x Subtract x from both sides.


y=-x-1 Rearrange the terms and simplify.


Now let's graph the equation:


Graph of y=-x-1.


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Now let's graph the two equations together:


Graph of y=x-1 (red). Graph of y=-x-1 (green)


From the graph, we can see that the two lines intersect at the point . So the solution to the system of equations is . This tells us that the system of equations is consistent and independent.