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Can the lengths 7.9 centimeters, 8.1 centimeters, and 5.3 centimeters form a right triangle?
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In a right triangle, there two shorter sides and a longest side.
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The longest side is across from the 90-degree angle.
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We call it the hypotenuse.
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Right triangles can use the Pythagorean theorem.
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The sum of the squares of the shorter sides is equal to the square of the longest side.
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So if we want to know if these three side lengths form a right triangle, we can use the Pythagorean theorem to decide.
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We will plug in 7.9 and 5.3 for the shorter sides and 8.1 for the longest side.
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So we have 5.3 squared plus 7.9 squared equals 8.1 squared.
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5.3 squared is equal to 28.09 and 7.9 squared is equal to 62.41.
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And finally 8.1 squared is equal to 65.61.
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Now we need to add 28.09 and 62.41, which is 90.50, and is that equal to 65.61?
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They are not equal.
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Therefore, these lengths cannot form a right triangle, so our answer is no.