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Solve for x and y using addition or substitution. 
2x -3y = 4   |Assuming the typo
2x + y = -4
2x -3y = 4   |Multiplying 2nd EQ by 3 to eliminate y
6x +3y = -4*3
  8x = -8
   x = -1   and y = -2  (y= -2x - 4)
CHECKING our Answer***
 2x -3y = 4 
 2*-1 - 3*-2 = -2 + 6 = 4