how to solve y² - 11y?

You need more help than you think !

this is an expression, not an equation ! As such, it can be factored, simplified, ...
but, it can't be solved !

y^2 - 11y = y(y - 11)

QED

Factorize.

y^2 - 11y
= y(y) - y(11)
= y(y - 11)

umm is there anything else all you can do is take a y out (y*(y-11)) unless theres another side of the equation if it = 0 the options are y=0 and y=11

dear solve it like this:

1step:
arrange it like this = -11y +y2

2 step:
you subtract 11 from i (y2 has a coefficient 1)

3step:
answer is -10y2

y² - 11y = 0
y(y - 11) = 0
y = 0 or y = 11

Well is it y2 - 11y = 0. If yes then since it is a quadratic equation you will have two roots.

y2 - 11y = 0
y ( y-11) = 0
y = 0 , 11

I mean you forget the 0 in second member

so y^2-11y =0

y*(y-11) =0

2 roots y=0 and y=11