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Triangle Calculator.

Solve missing sides, angles, area, and perimeter of any triangle from three parameters.

Input Parameters

Equilateral
Angles-
Area-
Perimeter-

Comments & Feedback.

Documentation

User manual & function guide.

Detailed manual explaining every function, input parameter, and operational example for the Triangle Calculator.

Sides (a, b, c)

Function

Side lengths of triangle.

Example Operation a = 3, b = 4, c = 5

Heron's Area Calculation

Function

Computes exact area and perimeter.

Example Operation a=3, b=4, c=5 -> Right Triangle, Area = 6.0, Perimeter = 12

Law of Cosines Angles

Function

Calculates internal angles in degrees.

Example Operation Angles: A = 36.87°, B = 53.13°, C = 90.00°

Frequently asked questions.

How is the area of a triangle calculated from three sides?

Using Heron's formula: first calculate the semi-perimeter s = (a+b+c)/2, then Area = √(s(s-a)(s-b)(s-c)). This works for any triangle when all three sides are known.

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