SOLUTION: y=x+1 8x-4y=0

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Question 147492: y=x+1
8x-4y=0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Start with the given system
8x-4y=0
y=x%2B1



8x-4%28x%2B1%29=0 Plug in y=x%2B1 into the first equation. In other words, replace each y with x%2B1. Notice we've eliminated the y variables. So we now have a simple equation with one unknown.


8x-4x-4=0 Distribute


4x-4=0 Combine like terms on the left side


4x=0%2B4Add 4 to both sides


4x=4 Combine like terms on the right side


x=%284%29%2F%284%29 Divide both sides by 4 to isolate x



x=1 Divide




Now that we know that x=1, we can plug this into y=x%2B1 to find y



y=%281%29%2B1 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+-8x%2F%28-4%29%2C+x%2B1%29+ Graph of 8x-4y=0 (red) and y=x%2B1 (green)