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==In navigation==
{{broader|Position fixing}}
When resecting or fixing a position, the geometric strength (angular disparity) of the mapped points affects the precision and accuracy of the outcome. Accuracy increases as the angle between the two position lines approaches 90 degrees.<ref>Seidman, David, and Cleveland, Paul, ''The Essential Wilderness Navigator'', Ragged Mountain Press (2001), {{ISBN|0-07-136110-3}}, p. 100</ref> Magnetic bearings are observed on the ground from the point under ___location to two or more features shown on a map of the area.<ref>Mooers, pp. 129–134</ref><ref>Kals, pp. 43–49</ref> Lines of reverse bearings, or ''lines of position'', are then drawn on the map from the known features; two and more lines provide the resection point (the navigator's ___location).<ref>Mooers, pp. 129–134</ref> When three or more lines of position are utilized, the method is often popularly (though erroneously) referred to as [[triangulation]] (in precise terms, using three or more lines of position is still correctly called ''resection'', as angular [[law of tangents]] ([[cotangent|cot]]) calculations are not performed).<ref>Touche, Fred, ''Wilderness Navigation Handbook'', Fred Touche (2004), {{ISBN|978-0-9732527-0-5}}, {{ISBN|0-9732527-0-7}}, pp. 60–67</ref> When using a map and compass to perform resection, it is important to allow for the difference between the magnetic bearings observed and grid north (or true north) bearings ([[
Resection continues to be employed in land and inshore navigation today, as it is a simple and quick method requiring only an inexpensive magnetic compass and map/chart.<ref>Mooers, pp. 129–134</ref><ref>Kals, pp. 43–49</ref><ref>Touche, pp. 60–67</ref>
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