Answer:
20 m
Explanation:
Assuming the given dimensions are the leg lengths of a right triangle, the hypotenuse is given by the Pythagorean theorem:
c² = a² + b²
c² = (12 m)² +(16 m)² = (144 m²) +(256 m²) = 400 m²
c = √(400 m²) = 20 m
The length of the hypotenuse is 20 m.
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You can recognize that the side length have the ratio 3:4, so are part of a 3:4:5 right triangle with a scale factor of 4 m. They hypotenuse is 5×4 m = 20 m.