The triangle is a fundamental polygon in geometry, architecture, and engineering. Calculating its properties—such as area, perimeter, and internal angles—is essential for spatial design, land surveying, and physics computations. Whether you are dealing with right-angled, isosceles, equilateral, or scalene triangles, utilizing standard geometric theorems ensures structural and mathematical accuracy in both academic and professional projects.
Key Triangle Formulas
Area: 1/2 × Base × Height (or Heron's Formula for 3 known sides)
Pythagorean Theorem (Right Triangles only): a² + b² = c²
How to Use This Calculator
- Select the specific values you want to calculate (e.g., Area, Perimeter, or Hypotenuse).
- Input the known variables, such as the base length, height, or known sides.
- If dealing with a right triangle, identify the legs (a and b) versus the hypotenuse (c).
- Click Calculate to instantly solve for the missing geometric values.
Frequently Asked Questions (FAQ)
What is Heron's Formula?
Heron's formula allows you to calculate the area of any triangle without knowing its height, as long as you know the length of all three sides. The formula is Area = √(s(s-a)(s-b)(s-c)), where 's' is the semi-perimeter (half of the total perimeter).
Do the internal angles of a triangle always add up to 180 degrees?
Yes, in standard Euclidean (flat) geometry, the three internal angles of any triangle will always sum to exactly 180 degrees (or π radians). If you know two angles, you can always find the third by subtracting their sum from 180.