若1/x-1/y=3,则(5x 3xy-5y)/(3x-xy-3y)=?(要用到‘分子分母同乘或同除一个数’的值不变)Thanks a lot是(5x+3xy-5y)/(3x-xy-3y)
问题描述:
若1/x-1/y=3,则(5x 3xy-5y)/(3x-xy-3y)=?(要用到‘分子分母同乘或同除一个数’的值不变)
Thanks a lot
是(5x+3xy-5y)/(3x-xy-3y)
答