Jawabanmu

2014-08-12T16:12:40+07:00
=  x -4y
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2014-08-12T16:13:21+07:00
9x+6y-10y-8x
= 9x-8x+6y-10y
= x-4y
9x + 6y - 10y - 8y
=9x-8x+6y-10y = x-4y
x-4y