Textedit Yosemite erase function In OS X Textedit, I was able to remove unwanted material from images scanned to JPEGs by using the select tool to define the area to be removed and then pressing "delete", resulting in a white area on a white background. How do I do that using Textedit Yosemite?
That can not be done with TextEdit application.

You were probably using the Preview and it will do as you say. 

Applications that allow you modifying the JPEG are many but the simplest one are Paintbrush or Gimp.