help me please

[CoolBlueR]

[o)]

I need help with this problem. I dont know what equation to use.

A 5.5g bullet is fired into a block of wood w/a mass of 22.6g.
The wood block is initially at rest on a 1.5m tall post. After
the collision, the wood block and bullet land 2.5m from the base of the post. What is the initial speed of the bullet?

I tried to do this myself but all I got was the givens, I had no idea of where to start!

[chroot]

Step 1: Use Newtonian mechanics to figure out how fast the block+bullet had to be moving horizontally to go 2.5 m in the time it took to fall 1.5 m.

Step 2: Use the conservation of linear momentum in a completely inelastic collision to find the initial speed of the bullet.

- Warren