Well, the Pythagorean Theorem states that a^2 + b^2 = c^2 when abc is a triangle, and c is the hypotenuse. Therefore, we have a = 15 and b = 18.
15^2 = 225
18^2 = 324
Adding them, we get c^2 = 549. So, the answer is the square root of 549, which, to the nearest tenth, is 23.4
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