How would I simplify this type of radical. I need to leave it in radical form. I don't know how to get high roots into low exponents under the radical?

If you need an equation, it would be y=2x+8, y would be how long it grew, x being weeks.if you need how long he was asleep, it would be 4 weeks if he started with no beard, the equation would be x=8÷2if he did have a beard before hand, the equation would be 2w+x=8

In my opinion i believe it’s a-kite