SOLUTION: Solve the system of linear equations by graphing and write an ordered pair 3x+y=0 4x-y=7

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Question 652408: Solve the system of linear equations by graphing and write an ordered pair
3x+y=0
4x-y=7
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

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



Start with the given system of equations:


3x%2By=0

4x-y=7





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


3x%2By=0 Start with the given equation



1y=0-3x Subtract 3+x from both sides



1y=-3x%2B0 Rearrange the equation



y=%28-3x%2B0%29%2F%281%29 Divide both sides by 1



y=%28-3%2F1%29x%2B%280%29%2F%281%29 Break up the fraction



y=-3x%2B0 Reduce



Now lets graph y=-3x%2B0 (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+-3x%2B0%29+ Graph of y=-3x%2B0




So let's solve for y on the second equation


4x-y=7 Start with the given equation



-y=7-4x Subtract 4+x from both sides



-y=-4x%2B7 Rearrange the equation



y=%28-4x%2B7%29%2F%28-1%29 Divide both sides by -1



y=%28-4%2F-1%29x%2B%287%29%2F%28-1%29 Break up the fraction



y=4x-7 Reduce





Now lets add the graph of y=4x-7 to our first plot to get:


+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+-3x%2B0%2C4x-7%29+ Graph of y=-3x%2B0(red) and y=4x-7(green)


From the graph, we can see that the two lines intersect at the point (1,-3) (note: you might have to adjust the window to see the intersection)