计算x—4y分之3x+4y4y—x分之x+y—x—4y分之7y得( )

问题描述:

计算x—4y分之3x+4y4y—x分之x+y—x—4y分之7y得( )

数学之美团为你解答
3x/(x-4y)+(x+y)/(4y-x) - 7x/(x-4y)
=3x/(x-4y) - (x+y)/(x-4y) - 7x/(x-4y)
=(3x-x-y-7x)/(x-4y)
=(-5x-y)/(x-4y)
=(5x+y)/(4y-x)