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Pythagoras Triangle Check

Right, acute, or obtuse from three sides.

Triangle is
right
a² + b² = c² (right triangle)

a² + b² = 25.00

c² = 25.00

For a right triangle: c = 5.0000

Common Pythagorean triples

  • 3, 4, 5
  • 5, 12, 13
  • 8, 15, 17
  • 7, 24, 25
  • 20, 21, 29
  • 9, 40, 41
  • 12, 35, 37
  • 11, 60, 61

Pythagorean theorem with a comparison: tells you whether a triangle with given sides is right, acute, or obtuse. Useful for carpentry (3-4-5 squaring) and quick geometry checks.

About

Enter three sides. The tool checks a² + b² vs c². Equal = right triangle. Sum of squares larger = acute triangle. Smaller = obtuse. Includes a list of common Pythagorean triples.

How to use

  1. Enter three sides.

FAQ

Why does carpentry use 3-4-5?+

It's the smallest Pythagorean triple. Lay out 3 ft, 4 ft, and check the diagonal is exactly 5 ft - your corner is square.