Baseline distance AB length, height h1 of the observer at points A and B.
Angles measured at A – Horizontal angle θ vertical angle α to object, and vertical angle δ slope of ground.
Angles measured at B – Horizontal angle φ and vertical angle β.
Solution: Height of object above ground at position A.
First, calculate horizontal distance A1B2.
In triangle A1C1B2, given the sine law:
In triangle A1C1E:
Finally, calculate height of object above ground at station A:
Combining the previous: