For Those That Are Math Minded

Yesterday was Ken’s birthday and in that spirit I have a math question for you all. Here is an actual math problem from Caity’s geometry text book. If you know the answer, leave a comment. I’d love to know who can do this. Here it is:


“Lewis Carroll once posed the following problem in a letter to a young friend who was studying algebra:

Understanding you to be a distinguished algebraist (i.e. distinguished from other algebraists by different face, different height, etc.) I beg to submit to you a difficulty which distresses me much.

If x and y are each equal to "1", it is plain that 2(x² -y² ) =0 and also that 5(x-y) =0.
Hence 2(x² -y² ) = 5(x-y)
Now divide each side of this equation by (x-y).
Then 2(x+y) = 5
But (x+y) = (1+1), i.e. =2.
So that 2 x 2 =5.

Ever since this painful fact has been forced upon me, I have not slept more than 8 hours a night, and have not been able to eat more than 3 meals a day. I trust you will kindly explain the difficulty."

Okay, that's the problem. So, who can solve it?

Ave Maria!
C.