SOLUTION: y=4x x+y=5

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Question 118572: y=4x
x+y=5
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

Start with the given system
x%2By=5
y=4x



x%2B1%284x%29=5 Plug in y=4x into the first equation. In other words, replace each y with 4x. Notice we've eliminated the y variables. So we now have a simple equation with one unknown.



5x=5 Combine like terms on the left side


x=%285%29%2F%285%29 Divide both sides by 5 to isolate x



x=1 Divide




Now that we know that x=1, we can plug this into y=4x to find y



y=4%281%29 Substitute 1 for each x


y=4 Simplify


So our answer is x=1 and y=4