Answer:

Explanation:
Use the Pythagorean Theorem
The equation for the Pythagorean Theorem is

* a and b are the lengths of the legs, and c is the hypotenuse.*
(To know which side is the hypotenuse look at longest side which is across the right angle).
a= x, b=8, c=9

Let's Plug in the side lengths:

Evaluate 8^2 and 9^2:

Subtract 64 from both sides:


Take the square root of both sides:

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