Question 622512
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Slant height has nothing whatever to do with a cylinder.  Now it is possible that they are talking about the slant height of a cone that has the same base and height as your cylinder.  Then you can use the slant height and the radius as the hypotenuse and one leg of a right triangle as inputs to Pythagoras so that you can get the height of the cone and thereby the height of the cylinder.

Hint: 5-12-13 is a Pythagorean triple.

John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
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