SOLUTION: please solve this linear equation using elimination. 5x/12 - y/6 = 3 x + 2y = 0

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Question 146516: please solve this linear equation using elimination.
5x/12 - y/6 = 3
x + 2y = 0

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
5x%2F12+-+y%2F6+=+3+ Start with the first equation.


12%285x%2Fcross%2812%29-y%2Fcross%286%29%29=12%283%29 Multiply both sides by the LCD 12


5x+-+2y+=+36 Distribute and multiply


So we now have the system of equations:

system%285x-2y=36%2Cx%2B2y=0%29




Now add the equations together. In order to add 2 equations, group like terms and combine them

%285x%2Bx%29%2B%28-2y%2B2y%29=36%2B0

Combine like terms and simplify



6x%2Bcross%28-2y%2B2y%29=36 Notice how the y terms cancel out




6x=36 Simplify


x=36%2F6 Divide both sides by 6 to isolate x


x=6 Reduce



Now plug this answer into the top equation 5x-2y=36 to solve for y

5x-2y=36 Start with the first equation


5%286%29-2y=36 Plug in x=6


30-2y=36 Multiply


-2y=36-30 Subtract 30 from both sides.


-2y=6 Combine like terms on the right side.


y=%286%29%2F%28-2%29 Divide both sides by -2 to isolate y.


y=-3 Reduce.


So our answer is
x=6 and y=-3



which also looks like




Now let's graph the two equations (if you need help with graphing, check out this solver)


From the graph, we can see that the two equations intersect at . This visually verifies our answer.




graph of 5x-2y=36 (red) and x%2B2y=0 (green) and the intersection of the lines (blue circle).