SOLUTION: I need help with solving this problem,please help y=3x+11 2x+3y=0

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Question 130971: I need help with solving this problem,please help
y=3x+11
2x+3y=0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

Start with the given system
2x%2B3y=0
y=3x%2B11



2x%2B3%283x%2B11%29=0 Plug in y=3x%2B11 into the first equation. In other words, replace each y with 3x%2B11. Notice we've eliminated the y variables. So we now have a simple equation with one unknown.


2x%2B9x%2B33=0 Distribute


11x%2B33=0 Combine like terms on the left side


11x=0-33Subtract 33 from both sides


11x=-33 Combine like terms on the right side


x=%28-33%29%2F%2811%29 Divide both sides by 11 to isolate x



x=-3 Divide




Now that we know that x=-3, we can plug this into y=3x%2B11 to find y



y=3%28-3%29%2B11 Substitute -3 for each x


y=2 Simplify


So our answer is x=-3 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+-2x%2F3%2C+3x%2B11%29+ Graph of 2x%2B3y=0 (red) and y=3x%2B11 (green)