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Drawing Lines in DrRacket

Recall that an image is oriented with respect to the x and y axis in the following way: 
                    (0,1)
(-1,1) +--------------*--------------+ (1,1)
       |			     |
       |			     |
       |			     |
       |			     |
       |			     |
       |			     |
       |			     |
(-1,0) *              * (0,0)        * (1,0)
       |			     |
       |			     |
       |			     |
       |			     |
       |			     |
       |			     |
       |			     |
(-1,-1)+--------------*--------------+ (1,-1)
                    (0,-1)

A line is produced by: 

     (line x0 y0 x1 y1)
where (x0, y0) and (x1, y1) are the line's endpoints.
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