Question

Find x. 6.5 cm x 2.5 cm Y= cm

Answer 1

9514 1404 393

Answer:

  x = 6.0 cm

Step-by-step explanation:

The ratio of the given dimensions is 2.5/6.5 = 5/13. This should give you a clue that the dimensions here are all half those of the (5, 12, 13) Pythagorean triple. That is, ...

  x = 12/2 = 6 . . . cm

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In case you haven't memorized a few of the Pythagorean triples commonly used in algebra problems*, you can figure x using the Pythagorean theorem:

  6.5² = 2.5² +x²

  42.25 -6.25 = x²

  x = √36 = 6

  x = 6.0 cm

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* most commonly seen are (3, 4, 5), (5, 12, 13), (7, 40, 41) and their multiples.