SOLUTION: what is x=y+4 2x+3y=43

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Question 175260This question is from textbook algebra 2
: what is x=y+4
2x+3y=43 This question is from textbook algebra 2

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Start with the given system

x=y%2B4
2x%2B3y=43




2%28y%2B4%29%2B3y=43 Plug in x=y%2B4 into the second equation. In other words, replace each x with y%2B4. Notice we've eliminated the x variables. So we now have a simple equation with one unknown.


2y%2B8%2B3y=43 Distribute


5y%2B8=43 Combine like terms on the left side


5y=43-8Subtract 8 from both sides


5y=35 Combine like terms on the right side


y=%2835%29%2F%285%29 Divide both sides by 5 to isolate y



y=7 Divide




Now that we know that y=7, we can plug this into x=y%2B4 to find x



x=%287%29%2B4 Substitute 7 for each y


x=11 Add


So our answer is x=11 and y=7 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+-8%2C+12%2C+-10%2C+10%2C+%28x-4%29%2F1%2C+%2843-2x%29%2F3%29+ Graph of x=y%2B4 (red) and 2x%2B3y=43 (green)