SOLUTION: Please help! 2x - 4y = 8 x - 2y = 4

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Question 264737: Please help!
2x - 4y = 8
x - 2y = 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%282x-4y=8%2Cx-2y=4%29


-2%28x-2y%29=-2%284%29 Multiply the both sides of the second equation by -2.


-2x%2B4y=-8 Distribute and multiply.


So we have the new system of equations:
system%282x-4y=8%2C-2x%2B4y=-8%29


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


%282x-4y%29%2B%28-2x%2B4y%29=%288%29%2B%28-8%29


%282x%2B-2x%29%2B%28-4y%2B4y%29=8%2B-8 Group like terms.


0x%2B0y=0 Combine like terms.


0=0Simplify.


Since 0=0 is ALWAYS true, this means that there are an infinite number of solutions.


So the system is consistent and dependent.