SOLUTION: 3x+y=4 9x+3y=6 using elimination

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Question 663284: 3x+y=4
9x+3y=6
using elimination
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%283x%2By=4%2C9x%2B3y=6%29


-3%283x%2By%29=-3%284%29 Multiply the both sides of the first equation by -3.


-9x-3y=-12 Distribute and multiply.


So we have the new system of equations:
system%28-9x-3y=-12%2C9x%2B3y=6%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:


%28-9x-3y%29%2B%289x%2B3y%29=%28-12%29%2B%286%29


%28-9x%2B9x%29%2B%28-3y%2B3y%29=-12%2B6 Group like terms.


0x%2B0y=-6 Combine like terms.


0=-6Simplify.


Since 0=-6 is never true, this means that there are no solutions.

So the system is inconsistent.