SOLUTION: i've tried several different ways and can not seem to get this question of elimination, 5y-7x=29 2y+x=4 the x should equal -2 and y should equal 3 i know this because i use

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Question 176030: i've tried several different ways and can not seem to get this question of elimination,
5y-7x=29
2y+x=4
the x should equal -2 and y should equal 3
i know this because i used substitution earlier for this question,

Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
Note: I've rearranged the terms to get the system






Start with the given system of equations:



Multiply the both sides of the second equation by 7.


Distribute and multiply.


So we have the new system of equations:



Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:





Group like terms.


Combine like terms.


Simplify.


Divide both sides by to isolate .


Reduce.


------------------------------------------------------------------


Now go back to the first equation.


Plug in .


Multiply.


Subtract from both sides.


Combine like terms on the right side.


Divide both sides by to isolate .


Reduce.


So our answer is and .


Which form the ordered pair .


This means that the system is consistent and independent.


Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.


Graph of (red) and (green)



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