SOLUTION: y=x-1 2x-y=0

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Question 127907: y=x-1
2x-y=0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

Start with the given system
2x-1y=0
y=x-1



2x-1%28x-1%29=0 Plug in y=x-1 into the first equation. In other words, replace each y with x-1. Notice we've eliminated the y variables. So we now have a simple equation with one unknown.


2x-1x%2B1=0 Distribute


x%2B1=0 Combine like terms on the left side


x=0-1Subtract 1 from both sides


x=-1 Combine like terms on the right side




Now that we know that x=-1, we can plug this into y=x-1 to find y



y=%28-1%29-1 Substitute -1 for each x


y=-2 Simplify


So our answer is x=-1 and y=-2 which also looks like



Notice if we graph the two equations, we can see that their intersection is at . So this verifies our answer.


+graph%28+500%2C+500%2C+-5%2C+5%2C+-5%2C+5%2C+2x%2C+x-1%29+ Graph of 2x-1y=0 (red) and y=x-1 (green)