Jawabanmu

2014-09-08T20:23:17+07:00
2x - 4x + 3y - 5y = -2x -2y
2x+3y-4x-5y=2x+4x+3y-5y=-2y+(-2y)=-2x-2y
2014-09-08T20:24:04+07:00
2x + 3y - 4x - 5y
dikelompokkan >> 2x - 4x + 3y - 5y
                            = -2x + (-2y)
                            = - 2x - 2y

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