SOLUTION: x+4y=-1 2x-4y=4

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Question 677236: x+4y=-1
2x-4y=4
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

Start with the given system of equations:
system%28x%2B4y=-1%2C2x-4y=4%29


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


%28x%2B4y%29%2B%282x-4y%29=%28-1%29%2B%284%29


%281x%2B2x%29%2B%284y%2B-4y%29=-1%2B4 Group like terms.


3x%2B0y=3 Combine like terms.


3x=3 Simplify.


x=%283%29%2F%283%29 Divide both sides by 3 to isolate x.


x=1 Reduce.


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x%2B4y=-1 Now go back to the first equation.


1%2B4y=-1 Plug in x=1.


4y=-1-1 Subtract 1 from both sides.


4y=-2 Combine like terms on the right side.


y=%28-2%29%2F%284%29 Divide both sides by 4 to isolate y.


y=-1%2F2 Reduce.


So the solutions are x=1 and y=-1%2F2.


Which form the ordered pair .


This means that the system is consistent and independent.