SOLUTION: Can you Please Help Me Solve This equation by using the substitution method? -x+y+0 y=4x+5

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Question 143104: Can you Please Help Me Solve This equation by using the substitution method?
-x+y+0
y=4x+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=0
y=4x%2B5



-x%2B%284x%2B5%29=0 Plug in y=4x%2B5 into the first equation. In other words, replace each y with 4x%2B5. Notice we've eliminated the y variables. So we now have a simple equation with one unknown.


3x%2B5=0 Combine like terms on the left side


3x=0-5Subtract 5 from both sides


3x=-5 Combine like terms on the right side


x=%28-5%29%2F%283%29 Divide both sides by 3 to isolate x



x=-5%2F3 Reduce




Now that we know that x=-5%2F3, we can plug this into y=4x%2B5 to find y



y=4%28-5%2F3%29%2B5 Substitute -5%2F3 for each x


y=-20%2F3%2B5 Multiply


y=-5%2F3 Combine like terms


So our answer is x=-5%2F3 and y=-5%2F3 which forms the point