Question 481710
{{{2*sqrt(20)-4*sqrt(5)=2*sqrt(4*5)-4*sqrt(5)=2*sqrt(4)*sqrt(5)-4*sqrt(5)=2*2*sqrt(5)-4*sqrt(5)=4*sqrt(5)-4*sqrt(5)=(4-4)*sqrt(5)=0*sqrt(5)=0}}}



So {{{2*sqrt(20)-4sqrt(5)=0}}}