Hansen's problem is a problem in surveying described as follows. From the position of two known but inaccessible points 
and 
, determine the position of two unknown accessible points 
and 
by bearings from 
, 
,
to 
and 
, 
, 
to 
.
Hansen's Problem
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References
Dörrie, H. "Annex to a Survey." §40 in 100 Great Problems of Elementary Mathematics: Their History and Solutions. New York: Dover, pp. 193-197, 1965.Referenced on Wolfram|Alpha
Hansen's ProblemCite this as:
Weisstein, Eric W. "Hansen's Problem." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/HansensProblem.html