A cannonball is fired horizontally with an initial velocity of 655 m/s from the end of a cliff 725 m high. How far in the x direction does the cannonball in the air before it hits the ground?

Hint: We know gravity is pulling it towards earth at a known rate. If this was dropped straight down, how long would it take to fall that far? With the given velocity and ignoring wind resistance, how far would it get in that time?

And no, I'm not going to do your homework for you :)