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One leg of a right triangle has a length of 7m. The other sides have lengths that are consecutive integers. Find the lengths

User Admit
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1 Answer

4 votes

Answer:

24 m, 25 m

Explanation:

You want the two sides of a right triangle that are consecutive integers when one side is 7 m.

Pythagorean theorem

Let the shorter side be represented by x. Then the longer side is x+1, and the Pythagorean theorem tells you ...

7² +x² = (x+1)²

49 +x² = x² +2x +1

48 = 2x . . . . . . subtract (x²+1)

24 = x

x+1 = 25

The other sides are 24 and 25 meters.

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Additional comment

You know that 7 is not the hypotenuse, because a 3-4-5 right triangle is the only right triangle with consecutive integer leg lengths and a hypotenuse of 7 or less. (The next nearest right triangle with consecutive leg lengths is {20, 21, 29}, with a hypotenuse of 29.)

You may recognize the side lengths as the Pythagorean Triple {7, 24, 25}, one of the triples commonly seen in algebra and trig problems.

User Bijesh
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