Triangle Input Values

Angle Unit:

Instructions:

Enter at least 3 values including at least one side length. The calculator will solve for all remaining sides and angles using triangle laws and properties.

Triangle Visualization

Enter values to see triangle

Triangle Solution

Side a
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Side b
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Side c
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Angle A
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Angle B
-
Angle C
-
Area
-
Perimeter
-
Inradius
-
Circumradius
-

Triangle Facts & Properties

  • The sum of all internal angles in a triangle is always 180° (or π radians)
  • The sum of any two sides must be greater than the third side
  • In a right triangle: a² + b² = c² (Pythagorean theorem)
  • Law of Sines: a/sin(A) = b/sin(B) = c/sin(C)
  • Law of Cosines: c² = a² + b² - 2ab·cos(C)
  • Area can be calculated using: ½×base×height, ½ab·sin(C), or Heron's formula