Surveying Triangulation Distance
Given baseline + 2 angles, find unknown distance via law of sines.
Result
Distances to point
113.05 (from A) / 122.67 (from B)
Angle C = 50.00°.
- Baseline c100
- Angle A60°
- Angle B70°
- Angle C50.0000°
- Side a (opposite A)113.0516
- Side b (opposite B)122.6682
Step-by-step
- Angle C = 180° − A − B = 50.00°.
- Law of sines: a/sin A = c/sin C.
- a = c × sin A / sin C = 113.052.
How to use this calculator
- Measure baseline + angles A and B.
- Read distances to target.
About this calculator
Triangulation: measure a baseline + the angles to a distant point from each end. Law of sines computes distances to the point. Foundation of all classical surveying. Used to map territories before GPS. Modern GPS replaces it for most uses, but triangulation remains relevant for archaeology, terrestrial laser scanning verification, and astronomy (parallax to nearby stars). Source: standard surveying textbooks.
Frequently asked
Baseline gives length scale. Angles alone yield only proportions (similar triangles).
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