General Triangle Solver

The ultimate tool to solve any triangle. Input three known values (e.g., SSS, SAS, ASA, AAS) and automatically calculate all missing sides, angles, area, and perimeter using the law of sines, law of cosines, and Heron's formula.

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About General Triangle Solver

Welcome to our General Triangle Solver, the ultimate online tool for solving any triangle. Whether you know three sides (SSS), two sides and an angle (SAS or SSA), or two angles and a side (AAS/ASA), our calculator will automatically determine all missing sides, angles, area, and perimeter. Perfect for students, teachers, engineers, and anyone working with triangles.

Key Features of Our General Triangle Solver

Universal Triangle Solution: Solve any triangle with just 3 known values.
Multiple Input Types Supported:
- SSS: Three sides known
- SAS: Two sides and the included angle
- ASA/AAS: Two angles and one side
- SSA: Two sides and a non-included angle (ambiguous case)
Complete Triangle Data: Calculate all six triangle elements (three sides and three angles).
Area Calculation: Automatic area computation using Heron's formula.
Perimeter Calculation: Instant perimeter computation.
Step-by-Step Solutions: Detailed explanations of the solving process using law of sines and law of cosines.
Triangle Validation: Automatic verification of triangle inequality and angle sum properties.
Interactive Visualization: Visual representation of your triangle.

Understanding Triangle Solution Methods

Our calculator uses proven mathematical methods to solve triangles:

The Law of Sines

The law of sines relates the sides of a triangle to the sines of its angles:

$$\frac{a}{\sin(A)} = \frac{b}{\sin(B)} = \frac{c}{\sin(C)}$$

This law is particularly useful when you know:

Two angles and one side (AAS or ASA)
Two sides and a non-included angle (SSA - ambiguous case)

The Law of Cosines

The law of cosines is a generalization of the Pythagorean theorem:

$$c^2 = a^2 + b^2 - 2ab\cos(C)$$ $$b^2 = a^2 + c^2 - 2ac\cos(B)$$ $$a^2 = b^2 + c^2 - 2bc\cos(A)$$

This law is essential when you know:

Three sides (SSS)
Two sides and the included angle (SAS)

Heron's Formula for Area

Once all three sides are known, the area can be calculated using Heron's formula:

$$\text{Area} = \sqrt{s(s-a)(s-b)(s-c)}$$

where $s = \frac{a + b + c}{2}$ is the semi-perimeter.

How to Use the General Triangle Solver

Enter Known Values: Input any three known values (sides or angles). Leave the unknown fields empty.
Side Naming Convention: Sides are labeled as a, b, and c.
Angle Naming Convention: Angles are labeled as A (opposite side a), B (opposite side b), and C (opposite side c).
Angle Units: Enter all angles in degrees.
Click Calculate: The calculator will automatically determine the triangle type and solve for all missing values.
View Results: See all six triangle elements, area, perimeter, and step-by-step solution.

Triangle Types and Solution Methods

SSS (Side-Side-Side): When three sides are known, use the law of cosines to find all three angles.
SAS (Side-Angle-Side): When two sides and the included angle are known, use the law of cosines to find the third side, then law of sines for remaining angles.
ASA/AAS (Angle-Side-Angle or Angle-Angle-Side): When two angles and one side are known, first find the third angle (angles sum to 180°), then use law of sines to find remaining sides.
SSA (Side-Side-Angle): The ambiguous case - may have 0, 1, or 2 solutions. Our calculator determines the valid solution when it exists.

Important Triangle Properties

Angle Sum: The sum of all angles in a triangle equals 180°: $A + B + C = 180°$
Triangle Inequality: The sum of any two sides must be greater than the third side:
- $a + b > c$
- $b + c > a$
- $a + c > b$
Largest Angle: The largest angle is opposite the longest side.
Smallest Angle: The smallest angle is opposite the shortest side.

Applications of Triangle Solving

Our triangle solver is especially useful for:

Geometry Education: Learning and teaching triangle properties and trigonometry.
Surveying: Land measurement and boundary determination.
Navigation: Distance and bearing calculations.
Engineering: Structural analysis, force calculations, and design.
Architecture: Roof pitch calculations, triangular structures.
Physics: Vector resolution and force diagrams.
Computer Graphics: 3D modeling and rendering.
Astronomy: Celestial navigation and parallax measurements.

The SSA Ambiguous Case

When you know two sides and an angle opposite one of them (SSA), there may be:

No Solution: No triangle exists with the given values.
One Solution: A unique triangle exists.
Two Solutions: Two different triangles can be formed (rare case).

Our calculator automatically detects this case and provides the appropriate solution when one exists.

Why Choose Our General Triangle Solver?

Solving triangles manually requires knowledge of multiple formulas and can be error-prone. Our calculator simplifies the process by providing:

Accuracy: Precise calculations using proven mathematical methods.
Speed: Instant results for any valid triangle configuration.
Educational Value: Step-by-step solutions help you understand the solving process.
Versatility: Handles all triangle types and input combinations.
Validation: Automatic checking of triangle validity and mathematical correctness.
Comprehensive Output: All triangle elements, area, and perimeter in one calculation.