How to Calculate the Bearing Angle

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A bearing angle describes an angle formed by two intersecting vectors whose degrees are measured clockwise from the northern point. Therefore, these angles will always follow a circular motion with parameters between zero and 360 degrees. For example, if a clock's hand pointed toward seven, the bearing angle would be 210 degrees. Professionals including pilots, captains and military personnel use bearing angles for compass navigation to quickly determine and relay direction and position.

Use basic trigonometry. A straight line indicates a 180-degree angle and a circle indicates 360 degrees. Using this information, if we know any other relative angle measurement, we can calculate the bearing angle. For example, a boat sails due east, meaning it is located precisely between a straight line and a total circle. Find the middle value by adding 180 to 360 and dividing by two. The bearing angle equals 270 degrees. If the boat had sailed 10 degrees north of east you would add 10, making the bearing equal 280 degrees.

Note the difference between direction and bearing. Direction uses the north-south line to reference the angle's east or west direction, so no angle should ever exceed 90 degrees. For example, if a clock's hand points to 11, that equals 30 degrees west of north; the bearing angle would equal 330 degrees. Direction is often known and the bearing angle must be derived. Determine where the exact point is on a graph and add the angles using the clockwise method.

Draw a diagram, which is usually the best method to approach a bearing problem, or any geometry problem. Word problems often contain too much information to address at once, and this may obscure an obvious solution. A graph with an x and y axis provides particular assistance. Bearings typically do not involve three dimensions, so such a graph on a Cartesian plane would prove accurate and explicit. Label the axes and note any excess information such as speed or magnitude, but usually these are not relevant when calculating bearing angles.

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