SOLUTION: How to solve y=2x-4 and y=x-2 in graphing .

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Question 924319: How to solve y=2x-4 and y=x-2 in graphing .
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

y=2x-4
y=x-2
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-2x%2By=-4
-x%2By=-2
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Solved by pluggable solver: Solve the System of Equations by Graphing



Start with the given system of equations:


-2x%2By=-4

-x%2By=-2





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


-2x%2By=-4 Start with the given equation



1y=-4%2B2x Add 2+x to both sides



1y=%2B2x-4 Rearrange the equation



y=%28%2B2x-4%29%2F%281%29 Divide both sides by 1



y=%28%2B2%2F1%29x%2B%28-4%29%2F%281%29 Break up the fraction



y=2x-4 Reduce



Now lets graph y=2x-4 (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+2x-4%29+ Graph of y=2x-4




So let's solve for y on the second equation


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



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



1y=%2Bx-2 Rearrange the equation



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



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



y=x-2 Reduce





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


+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+2x-4%2Cx-2%29+ Graph of y=2x-4(red) and y=x-2(green)


From the graph, we can see that the two lines intersect at the point (2,0) (note: you might have to adjust the window to see the intersection)