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Exterior Angle Calculator Triangle

Exterior Angle Formula:

\[ \text{Exterior Angle} = \text{Angle A} + \text{Angle B} \]

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1. What is the Exterior Angle Theorem?

The exterior angle theorem states that the measure of an exterior angle of a triangle is equal to the sum of the measures of the two non-adjacent interior angles. This fundamental geometric principle helps in solving various triangle-related problems.

2. How Does the Calculator Work?

The calculator uses the exterior angle formula:

\[ \text{Exterior Angle} = \text{Angle A} + \text{Angle B} \]

Where:

Explanation: The exterior angle is formed by extending one side of the triangle and is supplementary to the adjacent interior angle.

3. Importance of Exterior Angle Calculation

Details: Calculating exterior angles is essential in geometry for solving triangle problems, proving theorems, and understanding the properties of polygons. It's widely used in architecture, engineering, and various mathematical applications.

4. Using the Calculator

Tips: Enter the two non-adjacent interior angles in degrees. Both values must be positive and their sum must be less than 180 degrees to form a valid triangle.

5. Frequently Asked Questions (FAQ)

Q1: What is an exterior angle of a triangle?
A: An exterior angle is formed when one side of a triangle is extended. It lies outside the triangle and is adjacent to one of the interior angles.

Q2: Why does the exterior angle equal the sum of two interior angles?
A: This is a fundamental property of triangles proven by the exterior angle theorem, which is derived from the angle sum property of triangles.

Q3: Can the exterior angle be greater than 180 degrees?
A: No, in a triangle, the exterior angle is always less than 180 degrees because the sum of two interior angles is always less than 180 degrees.

Q4: How is this different from the interior angle sum?
A: The interior angle sum is always 180 degrees, while the exterior angle theorem deals with the relationship between an exterior angle and two non-adjacent interior angles.

Q5: Does this work for all types of triangles?
A: Yes, the exterior angle theorem applies to all triangles - equilateral, isosceles, and scalene triangles.

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