-3x + 6y =  -3 
-6x + 4y = -10

To eliminate x multiply the first equation by -2

 6x - 12y =   6 
-6x +  4y = -10
---------------
      -8y = -4
        y = 
        y = 

Start over:

-3x + 6y =  -3 
-6x + 4y = -10


To eliminate y multiply the first equation by 2
and the second equation by -3

-6x + 12y = -6 
18x - 12y = 30
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12x       = 24
        x = 
        x = 2

Solution (x,y) = (2,)