Question 631650
    Find a common solution for the system of equations -3y+12x=9 and x-y=0
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Given:
-3y+12x=9
x-y=0
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Reorder the first equation:
12x-3y=9
  x- y=0
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Multiply the second equation by -3 and add both equations together:
12x-3y=9
-3x+3y=0
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 9x   =9
  x  = 1
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substitute the above into:
x-y=0
1-y=0
-y=-1
y = 1
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Answer: x=1 and y=1