已知x、y满足根号下4x-5y+根号下x-y-1=0,则根号下xy-根号下x/y

问题描述:

已知x、y满足根号下4x-5y+根号下x-y-1=0,则根号下xy-根号下x/y
我已知道4x-5y=0,x-y-1=0 解得x=5,y=4 那后面怎么算?

√xy-√x/y
=√5·4-√5/4
=2√5-√5/2
=3√5/2