Calculating Speed of Ball After Racket Strike

[Kickbladesama]

Homework Statement

A 116 g ball is traveling to the left with a speed of 34 m/s when it is struck by a racket. The force on the ball, directed to the right and applied over 21 ms of contact time, is shown in the graph. What is the speed of the ball immediately after it leaves the racket?

this graph comes with it
http://www.webassign.net/grr/p7-16.gif

Homework Equations

I know it has something to do with impluse so I = F x T

The Attempt at a Solution

i have no idea!

 

[Rake-MC]

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

area under the graph = impulse, divide by mass = velocity

 

[Mentallic]

Yes, that formula is needed since $$I=\Delta \rho$$ where $$\Delta \rho$$=change in momentum.
All you need to do to find the impulse is calculate the area under the graph.