root(40) -2root(5)/root(10)
root(5)/root(10)=root(5/10)=root(1/2)=root(2) /2...0.707106781
2*this=root(2)=1.414213562
root(40)=root(4)*root(10)=2*root(10)=2*3.16227766
or 6.32455532
root(40 -2*root(5)/root(10)=6.3245532 - 1.414213562
But wot if yu shood hav sed [root(40) -2*root(5)]/root(10)...thats different story