SOLUTION: Solve the system by substitution. 5x + 5y = 0 y = –3x – 2

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Question 114177: Solve the system by substitution.
5x + 5y = 0
y = –3x – 2
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

Start with the given system
5x%2B5y=0
y=-3x-2



5x%2B5%28-3x-2%29=0 Plug in y=-3x-2 into the first equation. In other words, replace each y with -3x-2. Notice we've eliminated the y variables. So we now have a simple equation with one unknown.


5x%2B-15x-10=0 Distribute


-10x-10=0 Combine like terms on the left side


-10x=0%2B10Add 10 to both sides


-10x=10 Combine like terms on the right side


x=%2810%29%2F%28-10%29 Divide both sides by -10 to isolate x



x=-1 Divide




Now that we know that x=-1, we can plug this into y=-3x-2 to find y



y=-3%28-1%29-2 Substitute -1 for each x


y=1 Simplify


So our answer is x=-1 and y=1