1) 5x/12=(2x-1)/4-1=(2x-5)/4,然后两边同时乘以12,得5x=3(2x-5)=6x-15,所以x=15
2)两边同时乘以3,得3(1-y)=6-(2y-1), 3-3y=7-2y, 所以y=-4
3)两边同时乘以12,得4(2y-1)—2(10y+1)=3(2y+1)—12,
8y-4-20y-2=6y+3-12, 得-18y=-3 ,所以y=1/6
4)两边同时乘以6,得2[3y-(10-7y)/2]-3[2y-(2y+2)/3]=3y-6,
则6y-10+7y-6y+2y+2=3y-6,6y=2,所以y=1/3