Verified answer

you can factor this into:

sqrt(x) [sqrt(x) - 2] = 0

Thus sqrt(x) = 0 or [sqrt(x) - 2] = 0

The first case means x = 0

The second case means sqrt(x) = 2 or x = 4.

Thus the two solutions are 0 and 4.

so it is

x = 2 sqrt(x)

squaring both sides

x^2 = 4x

which is like

x^2 - 4x = 0

which gives

x(x-4) = 0

hence x = 0 or x = 4

x=2rad(x), x>=0

x^2=4x

x^2-4x=0

x(x-4)=0

x=0 or x=4