Question: Expanding a single dimension of a Part

Hi,

I am new to SolidWorks and was having trouble with adjusting a single dimension of a part that I made. I simply want to make the part wider, but have not figured out how to do so.

My single part was created by piecing together many smaller parts into an assembly and then using this link http://help.solidworks.com/2012/English/solidworks/sldworks/creating_a_joined_part.htm to join them into a single part (not sure if this information helps at all).

Thanks in advance.

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