SOLUTION: Solve the system by substitution. 5x + 3y = –19 y = –2x – 8

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Question 112104: Solve the system by substitution.
5x + 3y = –19
y = –2x – 8
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Start with the given system
5x%2B3y=-19
y=-2x-8



5x%2B3%28-2x-8%29=-19 Plug in y=-2x-8 into the first equation. In other words, replace each y with -2x-8. Notice we've eliminated the y variables. So we now have a simple equation with one unknown.


5x%2B-6x-24=-19 Distribute


-x-24=-19 Combine like terms on the left side


-x=-19%2B24Add 24 to both sides


-x=5 Combine like terms on the right side


x=%285%29%2F%28-1%29 Divide both sides by -1 to isolate x



x=-5 Divide




Now that we know that x=-5, we can plug this into y=-2x-8 to find y



y=-2%28-5%29-8 Substitute -5 for each x


y=2 Simplify


So our answer is x=-5 and y=2