Which of these four sets of side lengths will form a right triangle? Set 1 4 cm, 5 cm, 6 cm Set 2 8 in., 12 in., 20 in. Set 3 10 mm, 20 mm, 30 mm Set 4 12 ft, 16 ft, 20 ft

For a right triangle, the two shorter sides must satisfy the Pythagorean theorem: a² + b² = c², where c is the longest side. For Set 4, 12² + 16² = 144 + 256 = 400, and 20² = 400. Therefore, Set 4, with side lengths 12 ft, 16 ft, and 20 ft, forms a right triangle.

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