Triangle Exterior Angles Calculator
Calculate all three non-reflex exterior angles from two interior angles of a triangle.
Formula
C=180°−A−B; exterior A=180°−A; exterior B=180°−B; exterior C=A+B
Interior C ≈ 180-(50)-(60) · Exterior at A ≈ 180-(50) · Exterior at B ≈ 180-(60) · Exterior at C ≈ (50)+(60)
How to use
- Enter interior angle A in degrees.
- Enter interior angle B; A+B must be below 180°.
- Read C and the exterior angle at each vertex.
Examples
- A=50°, B=60° gives exterior angles 130°, 120°, 110°.
Frequently asked questions
Which exterior angle is used?
The angle between one side and the extension of the adjacent side.
What is their sum?
One such exterior angle at each vertex sums to 360°.
Are straight or degenerate triangles allowed?
No. All interior angles must be positive.
Sources
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