Triangle Ratio Calculator

Calculate triangle angles from ratios or find angle ratios from given angles

Triangle Ratio Calculator

Angle Ratio (x : y : z)

Enter the ratio components. For example, for ratio 2:3:4, enter x=2, y=3, z=4

Example Calculations

Example 1: Ratio 2:3:4

Given ratio: 2:3:4

Step 1: Find x = 180° ÷ (2+3+4) = 180° ÷ 9 = 20°

Step 2: Calculate angles:

• α = 2 × 20° = 40°

• β = 3 × 20° = 60°

• γ = 4 × 20° = 80°

Result: Angles are 40°, 60°, 80°

Example 2: Right Triangle 1:1:2

Given ratio: 1:1:2

Step 1: Find x = 180° ÷ (1+1+2) = 180° ÷ 4 = 45°

Step 2: Calculate angles: 45°, 45°, 90°

Result: This is a right isosceles triangle!

Common Triangle Ratios

1:2:3 (30-60-90)

Angles: 30°, 60°, 90°

Right triangle with special properties

1:1:2 (45-45-90)

Angles: 45°, 45°, 90°

Right isosceles triangle

1:1:1 (60-60-60)

Angles: 60°, 60°, 60°

Equilateral triangle

3:4:5

Angles: 45°, 60°, 75°

Scalene triangle

Key Formulas

Angle Sum

α + β + γ = 180°

Ratio to Angles

x = 180° ÷ (a + b + c)

Law of Sines

a/sin(α) = b/sin(β) = c/sin(γ)

Ratio Simplification

Divide by GCD of all terms

Understanding Triangle Ratios

What are Triangle Ratios?

Triangle ratios express the relationship between angles in a triangle. If angles are in the ratio a:b:c, we can write them as ax, bx, and cx, where x is a constant. Since angles in a triangle sum to 180°, we can solve for x and find all angles.

Applications

  • Finding missing angles when ratio is known
  • Simplifying angle relationships
  • Identifying special triangles
  • Solving geometry problems

Step-by-Step Method

Given ratio a:b:c

1. Write angles as ax, bx, cx

2. Use: ax + bx + cx = 180°

3. Simplify: (a + b + c)x = 180°

4. Solve: x = 180° ÷ (a + b + c)

5. Calculate: α = ax, β = bx, γ = cx

Note: This method works because the sum of angles in any triangle is always 180°, a fundamental property of Euclidean geometry.