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Diagonal of a rectangle
By france2031 on September 22, 1998:

Could you please help a senior citizen out by answering this simple (I'm sure for you) question If I have a rectangle that is 100 feet wide and 120 feet long how do I find how many feet it is from corner to corner? I am decorating a llama tent for the state fair and since it has been 40 or so years since I took geometry and I have search the web to no avail could you just give me the answer

Thank you so much
france2031@aol.com

By Harry on October 5, 1998:

From: Harry
At: Anonymous
On: 10/5/1998 at 19:38

This is a simple application of Pythagoras' theorem: the square on the hypotenuse is equal to the sum of the squares on the other two sides. Hence the length of the diagonal is

Square root of [100x100 + 120x120]

which comes to (cue much counting on fingers) 156.2 feet to 1 d.p.

Yours
Harry