# Physics 11 help please ?

## Homework Statement

A 55 kg student wearing skates stands at rest on a frictionless horizontal ice surface. She throws a 10 kg backpack horizontally with a speed8.3 m/s .
What is the velocity of the student after she throws the backpack?

## Homework Equations

F$$\Delta$$t = m$$\Delta$$v

## The Attempt at a Solution

so the answer should be 1.5 m/s [N] and i got this by dividing 10 kg (backpack) by 55 kg (student) and then multiplying that answer by 8.3 m/s . is this the right way or is there a proper formula i should follow?
thanks !