How do I trim the length of PVC pipe?

I have plumbing coming into my condo from the wall next to where the sink was. I am remodeling my kitchen, and the new sink is being placed 5" to the left. The water pipes aren't an issue, but the drain pipe is, it's now 5" too long and I need to shorten it. Obviously I can hack off the 5" inches of the horizontal pipe, but my question is how do I the reconnect it? What tools do I need? Here is a picture of the situation: http://ninebabcock.com/sink.jpg

Public Comments

1. You can get a coupling and cut out the required length of pipe. Then, using the coupling, glue the two sections of pipe back together. Make sure you make your cuts in the straight section of the pipe and that you leave enough room to glue the two ends back together. Need to make straight cuts and then prep the ends before gluing.
2. You need to buy a coupling (straight piece of pipe having inside diameter same as outside of existing pipe) and some PVC adhesive. Cut a section out of the drain pipe, put the coupling and end piece on to check that the dimension is right, and glue the pieces together.
3. the easiest way is to cut the pipe to the required length and install a new 90 degree elbow you will need a hacksaw a 90 PVC glue and cleaner and a level Cut the pipe to the new location clean the outside of the pipe and the inside of the 90 glue both cleaned areas and slide the 90 on twisting as you go to ensure a good seal before the glue dries place the level on the face of the 90 so that it is staright up and down and make sure the bubble is between the lines at the top of the level