In a classical triangulation, the procedure for third order, class II accuracy positioning requires how many directions?

• A. 4
• B. 8
• C. 12
• D. 2

Answer: (D)

Two directions are enough because each direction from the unknown point to a known station defines a line along which the point must lie. The intersection of two such lines fixes the location uniquely in the plane. For third-order, class II accuracy, this angular information provides the required precision without extra observations. A single direction would only locate the point somewhere along a line, while more directions would add redundancy beyond what this accuracy class requires. As long as the two reference lines aren’t parallel, their intersection gives the position exactly.