Yes it is possible. There are a few ways you can do it.

1. Use a wired router and connect ethernet cables from the router to the laptop and from the router to the PC. Advantages of this are fast, always on connection. Disadvantages of this are lots of wires and no portability with your laptop.

2. Use a wireless router and connect both computers wirelessly to the router. Advantages of this are fast, always on connection with no wires. Disadvantages and issues of this are you need to ensure that you properly configure your wireless router so that it is secure and wireless connections are slower than wired but this isn't really an issue because the speed is still high for both of them.

3. Use a cross over cable and connect one end to the Ethernet port of your laptop and one end to the Ethernet port of your PC. You will then be able to share files and printers between the two computers and share an internet connection. Advantages are that you don't need to buy a router. Disadvantages are wires, the computer with the connection to the internet has to be turned on for the computer that is sharing the connection to be able to connect to the internet.

Hope this helps