Hiding Left Menu from your page

There are three approaches you need to know about this subject.

First Approach:

From the configuration side you can hide the Quick Launch menu from the Site Settings in the Look and Feel section where there is TreeView which includes the settings to Show/Hide TreeView or Quick Launch menu.

Second Approach

In the first approach only the Quick Launch will be hidden but the Left Navigation Area will still appear with the Recycle Bin link and this is not what you want so what could you do?

You can create a new Page Layout  and include an empty asp:Contant element in its HTML code with the PlaceHolderId set to "PlaceHolderLeftNavBar" and the whole navigation area will be hidden in any page using the Page Layout you just created.

Third Approach

You need to hide the Left Navigation Area from an existing Page Layout in some pages only so what could you do?

You can add a Content Editor webpart and in its HTML Content add the following:
<style>
#s4-leftpanel
{
display:none;
}
</style>

Then publish the page...
If you face any problem related to this subject or have any comment please add your comment below and I will reply to you as soon as possible...