Question 474076
{{{2* sqrt (5/7) - 3* sqrt( 7/5)+ sqrt(140)=2sqrt(5)/sqrt(7)-3sqrt(7)/sqrt(5)+sqrt(4*5*7)=(2*sqrt(5)*sqrt(5)-3*sqrt(7)*sqrt(7)+2sqrt(5*7)*sqrt(5)*sqrt(7))/(sqrt(5)*sqrt(7))=(2*5-3*7+2*5*7)/sqrt(35)=59/sqrt(35)=(59*sqrt(35))/35}}}