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Pythagorean theorem

Adapted from Wikipedia · Explorer experience

Illustration of the Pythagorean theorem. The sum of two squares whose sides are the two legs (blue and red) is equal to the area of the square whose side is the hypotenuse (purple).

The Pythagorean Theorem

The Pythagorean theorem is a fun idea in mathematics. It helps us learn about special shapes called right triangles. A right triangle has one corner with an angle of exactly 90 degrees. The longest side, called the hypotenuse, is opposite this corner.

This theorem tells us something cool about the lengths of the sides. If we take the lengths of the two shorter sides and square them (multiply each by itself), their sum will equal the square of the hypotenuse. We can write this as a simple equation: a² + b² = c². Here, a and b are the two shorter sides, and c is the hypotenuse.

The theorem is named after a wise man from Greece, Pythagoras, who lived a long time ago. But guess what? People in many places, like India, China, and even older lands, knew about this idea before him.

The Pythagorean theorem is very useful. It helps us find distances on maps or in our everyday lives. For example, if we know the width and height of a rectangle, we can find the length of the diagonal using this theorem. Isn’t that amazing?

Images

An ancient Babylonian clay tablet showing mathematical calculations, used for teaching geometry and numbers.
An ancient Chinese diagram illustrating the Pythagorean theorem, showing how squares relate to the sides of a triangle.
An animated proof of the Pythagorean theorem showing how shapes can be rearranged to demonstrate the famous math rule.
The Western side of the Parthenon, an ancient Greek temple located in Athens.
An animated illustration showing a geometric proof of the Pythagorean theorem.
Animation showing how the Pythagorean theorem works by rearranging triangles to prove that a² + b² = c².
An animated illustration showing a creative proof of the Pythagorean theorem, a key concept in geometry.

This article is a child-friendly adaptation of the Wikipedia article on Pythagorean theorem, available under CC BY-SA 4.0.

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