Slipping problem

a bowling ball is slipping woth initial velocity of 5m/s with coeficient of friction being .08.
how far does it travel before it started to slip?

i used conservation of total energy and accounted for the energy lost in friction until it starts to roll.

both i and my teacher got double the actual answer of the problem.

i think i need to know the force that keeps the ball from rolling for the duration of x.
but im not completely sure, does anyone know how to use conservatin of total energy?

 

the answer is 7.8 meters if anyone was wondering

 

i used V=Rw to solve it correctly, you should get 7.8m

but i wnat to know how to use conservbation of total energy because it makes conceptual sense but it does not provide the correct answer.

 

(edit to the first post by me)

*a bowling ball is sliding without rolling with initial velocity of 5m/s and coeficient of friction being .08.
how far does it travel before it starts to roll?*

that should make more sense