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The Pythagorean theorem is used daily by builders, architects, GPS systems, and game developers. Recognising right triangles in real situations unlocks many useful calculations.
The Formula
c = √(a² + b²) | a = √(c² − b²)
Standard formula used by professionals worldwide
Worked Example
Step-by-step
Builder checking corner: 3m along wall A, 4m along wall B → diagonal should be 5m for perfect right angle
Key Concepts
- Accuracy: Results are as accurate as the inputs you provide
- Units: Always use consistent units throughout your calculation
- Verification: Double-check important calculations before making decisions
- Professional advice: For major financial, health, or structural decisions, consult a qualified professional
Privacy and Security
- All calculations run entirely in your browser
- No data is sent to any server
- No sign-up or personal information required
- Your data stays private — always
Frequently Asked Questions
How builders use it?
3-4-5 check: if diagonal is 5 when sides are 3 and 4, the corner is perfectly square.
GPS and Pythagoras?
GPS extends to 3D: d = √(x²+y²+z²) to calculate distances between coordinates.
45-45-90 triangle?
Equal legs. Hypotenuse = leg × √2. Common in construction and design.