Answer:

Explanation:
We'll use the Pythagorean Theorem
Equation:

where a and b are the lengths of the two legs of triangle, and c is the hypotenuse.
*A and b can be switched because they are legs*

Plug in the side lengths:

Evaluate 5^2 and 8^2:

Add 25 and 64 = 89

Now, take the square root of each side:

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