I have a dell optiplex GX110 and I want to look at the CPU how do I remove computer case?

I'm in a home study course for computer repair.I have a dell optiplex GX110 and I want to look at the CPU how do I remove computer case?
Here is a guide





http://support.dell.com/support/edocs/sy鈥?/a>I have a dell optiplex GX110 and I want to look at the CPU how do I remove computer case?
Dells are tool-less cases, meaning you don't need tools to open them.





If you have a tower, look for catches or large buttons in the case at the top rear, or on the sides at the back. Press and swing open the case. Other types, like desktop machines, might have slide-off cases. Just find the catches. Note that it can sometimes take some physical effort to open the case.
if it's a desktop model then there is a button on the left and right sides of the case towards the back. press those buttons and lift the back of the case up.