I'm having difficulty figuring #2 of this prob;em. I'm utterly clueless. Can someone explain it? Please and thank you.

y=x
2. List the roots of the function.

when is y equal to 0 ?

when x = 0

If the function had been
y = x^2 - x
then you would have said the roots of the function were
x = 0 and x = 1
because
y = x (x-1)
which is 0 when x = 0 and when x = 1