How to Use the Pythagorean Theorem to Find the Hypotenuse with Sides 15 cm and 12 cm

Step-by-step guide to solving for the hypotenuse 'A' using the Pythagorean theorem when the legs of a right triangle measure 15 cm and 12 cm.

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The Pythagorean theorem states that in a right-angled triangle, the square of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the other two sides. The formula is:

A² = B² + C²

Here, you are given two sides:

  • B = 15 cm
  • C = 12 cm

You want to find A, the hypotenuse.

Step 1: Square both known sides.

15² = 225

12² = 144

Step 2: Add the squares of the two sides.

225 + 144 = 369

Step 3: Take the square root of the sum to find A.

A = √369 ≈ 19.21 cm

Answer: The length of the hypotenuse A is approximately 19.21 centimeters.

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