Do you measure the tv frame from corner to corner of inside the frame from corner to corner?

Hmm. Just place a ruler so one edge is at one corner and then swing the ruler around to the opposite corner and read the distance.Is that what you meant?Answer 2 Why don't you just put a ruler from...

This length (diagonal) = sq.rt ( l2 + b2 ) where 'l' is length of the rectangle and 'b' is the breadth of the rectangle.

Yes, however usage may vary slightly. For instance, if you were getting directions by phone you might say, I'm at the corner of...... If you were just hanging out, you might say, I'm on the corner.

Speakers' Corner.

there isnt