Respuesta :

Answer: 4.12 km

Step-by-step explanation:

Use the Pythagorean theorem.  Name the hypotenuse (longest side) c and the bottom side b.  Then, simplify and solve for a.

a^2 + b^2 = c^2

a^2 + 8^2 = 9^2

a^2 + 64 = 81

a^2 = 17

a = square root of 17 or approx. 4.12

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