Okay so after Kevin folds the paper along its diagonal, then the two legs of the triangle are 12 inches long.
Here is a rule for a 45-45-90 triangle you can apply...
set the legs of a triangle equal to a variable.... (x)
the rule states that the sides of a 45-45-90 triangle are x, x, and x√2
so if we apply that to Kevin's triangle... the hypotenuse is 12√2
I hope this helps! :D
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