calculatorplustools.com

Pythagorean Theorem Calculator

Easily find the missing side of any right-angled triangle. Just enter the two sides you know.

a b c

What is the Pythagorean Theorem?

The Pythagorean theorem is a fundamental principle in geometry that states the relationship between the three sides of a right-angled triangle. It's named after the ancient Greek mathematician Pythagoras, and his theorem is elegantly simple yet incredibly powerful. It forms the basis for many calculations in fields like construction, engineering, navigation, and design. Our calculator simplifies this process, allowing you to quickly solve for any missing side of a right triangle.

The Formula: a² + b² = c²

The theorem is expressed by the famous equation:

a² + b² = c²

Where:

  • a and b are the lengths of the two shorter sides of the triangle, known as the "legs". These are the sides that form the 90-degree angle.
  • c is the length of the longest side, opposite the right angle, known as the "hypotenuse". The hypotenuse is always the longest side of a right triangle.

This hypotenuse calculator is pre-set to solve for 'c', but you can easily rearrange the formula to solve for 'a' or 'b' if you already know the length of the hypotenuse and one other side. This is crucial for problems where you know the diagonal distance but need to find a horizontal or vertical length.

Real-World Applications

The Pythagorean theorem is not just a concept for math class; it's used to solve practical problems every day:

  • Construction: Builders use it to ensure walls are perpendicular ("square") by creating a 3-4-5 triangle. If a triangle has sides of 3, 4, and 5 units, it must be a right triangle. This is essential for laying foundations and framing buildings.
  • Navigation: Pilots and ship captains can use it to calculate the shortest distance between two points (the hypotenuse) based on their northward and eastward travel distances.
  • Design & Graphics: It's used in computer graphics and design to calculate distances and place objects on a 2D plane, for example, determining the diagonal size of a screen.
  • Related Tools: The principles here are foundational for other geometric calculations. For instance, finding the sides of a triangle is often the first step before using an Area Calculator to determine its surface space.