-(5x+y)-7(x-y) -2分之1(x+y)+4分之1(x+2y) 4x-2(x-2) -2x-(3x-1) x-(5x-2y)+2(2x-y)
问题描述:
-(5x+y)-7(x-y) -2分之1(x+y)+4分之1(x+2y) 4x-2(x-2) -2x-(3x-1) x-(5x-2y)+2(2x-y)
答
-(5x+y)-7(x-y) -2分之1(x+y)+4分之1(x+2y)= -5x-y-7x+7y-x/2-y/2+x/4+y/2= -12x-x/4+6y= 6y-49x/44x-2(x-2) -2x-(3x-1) =4x-2x+4-2x-3x+1=5-3xx-(5x-2y)+2(2x-y)=x-8x+2y+4x-2y= -3x