HDTV Surprise!

How were your holidays?  Your school vacation?  Mine was good. I surprised my family with this HDTV, which I wrapped and hung on our wall.  The size of an HDTV is determined by the length of its diagonal. What size HDTV could this be?  Knowing that HDTV dimensions follow a 16:9 ratio (L & W), do you think this could be an HDTV?  No scale is provided, how can you make your own?  Note: This task can be solved with or without the use of the Pythagorean Theorem.