Mr Calcu | Instantly solve right triangle sides and simplify geometry with ease.

Quickly solve triangle sides using the Pythagorean theorem. Discover, calculate, and master geometry with ease and confidence in seconds.

Pythagorean Theorem Calculator

Pythagorean Theorem Calculator Guidelines

You're just one step away from solving your triangle—here’s how:

Usage Instructions

  • Enter any two known values of the triangle — either both legs or one leg and the hypotenuse.
  • Leave the unknown side empty. The calculator will solve for it automatically.
  • Only non-negative real numbers are allowed.
  • The hypotenuse must be the longest side; otherwise, results will be invalid.
  • The calculator displays answers up to 6 decimal places for precision.
Important Notes
  • If the output is irrational (e.g., √2), the calculator shows its decimal form.
  • For 3D distance, use a different formula:
    √(x² + y² + z²)

Pythagorean Theorem Calculator Description

What Is the Pythagorean Theorem?

The Pythagorean Theorem is a fundamental concept in geometry that defines the relationship between the sides of a right-angled triangle. It is a cornerstone in mathematics, especially in geometry and trigonometry.

Formula

c² = a² + b²
  • a and b are the legs (shorter sides).
  • c is the hypotenuse (longest side opposite the right angle).

Where It’s Used

  • Architecture & Engineering: Calculating ramp lengths, roof slopes, and distances.
  • Physics: Resolving vector components and motion analysis.
  • Surveying: Determining straight-line distances between two points.
  • Computer Graphics: Calculating pixel distances and object positioning.

How It Works

Depending on which values you have, the theorem works in two directions:

  • Finding Hypotenuse: If you know both legs:
    c = √(a² + b²)
  • Finding a Leg: If you know one leg and the hypotenuse:
    a = √(c² - b²)

Visual Interpretation

Imagine squares built on each side of the triangle. The area of the square on the hypotenuse is equal to the combined areas of the other two squares. This offers a powerful geometric interpretation of the formula.

Edge Case Handling

  • Zero-Length Side: One leg is 0 → the hypotenuse equals the non-zero leg.
  • All Zeros: Not a valid triangle; the result is 0 but meaningless geometrically.
  • Very Large Inputs: Input values like 1e9 may work, but ensure calculator precision is adequate.
  • Irrational Outputs: Inputs such as 1 and √3 yield irrational hypotenuses; outputs are given in decimal form.
  • Invalid Triangle: If the hypotenuse is shorter than a leg, an error or NaN is returned.

Case Study Examples

1. Accessibility Ramp Design

An architect must design a ramp with a 3-foot rise and 4-foot run. Applying the theorem:

c = √(3² + 4²) = √25 = 5 ft

This confirms the ramp meets code requirements.

2. Land Surveying

A surveyor needs the direct distance between two uneven land points. One leg is 150 meters, the other 200 meters:

c = √(150² + 200²) = √62500 = 250 m

This determines where to place boundary markers with precision.

Fun Fact

The Pythagorean Theorem was known to the Babylonians long before Pythagoras. However, Pythagoras was the first to provide a formal proof.

Start calculating now to take the guesswork out of right triangle problems and get accurate answers in seconds!

Example Calculation

a (leg)b (leg)c (hypotenuse)
345
51213
72425
1√32
099
81517
000
100000000010000000001414213562.373

Frequently Asked Questions

A² + b² = c², where 'a' and 'b' are legs, and 'c' is the hypotenuse.

Enter two sides, leave one blank, and click 'Calculate'.

Yes. The calculator supports decimal values and will provide accurate approximations for irrational results.

No. The Pythagorean theorem only applies to right-angled triangles.

The calculator will return an error or undefined result because the values do not form a valid right triangle.

When the computed value is irrational (like √2 or √3), the calculator provides a decimal approximation rounded to several digits.

This specific calculator is for 2D right triangles. For 3D, use the 3D distance formula: <code>√(x² + y² + z²)</code>.

Use the formula √(a² + b²) with both legs known — it's the quickest method for right triangles.

Our Other Tools