A second reference station** P** is far but visible from T. By occupying reference station T, measure angles τ’ and θ. From station B, measure angle **β**’ and from station **A**, measure angle **α’**. Finally, measure distance **(BA)**.

1. Angle measurements include uncertainties, causing inaccurate result on the sum of triangle angles.

τ' +β' '+α' -200gon= w

Equally distribute discrepancy **w** and correct values for all angles measured:

and

τ+β+α=200gon

2. By applying the Second Fundamental Surveying Problem and the known coordinates of reference stations **T** and **P**, calculate the **bearing angle TP**:

Then, calculate bearing angles **TB** and **TA**:

4. Considering the known coordinates of reference station T and applying the equations of the First Fundamental Surveying Problem: