document.write( "Question 460692: A plane travels 160 miles at a heading of N 33 degrees W. It then changes direction and travels 205 miles at a heading of N 49 degrees W. How far is the plane from it's original position? \n" ); document.write( "
Algebra.Com's Answer #316032 by lwsshak3(11628) ![]() You can put this solution on YOUR website! A plane travels 160 miles at a heading of N 33 degrees W. It then changes direction and travels 205 miles at a heading of N 49 degrees W. How far is the plane from it's original position? \n" ); document.write( ".. \n" ); document.write( "I don't have the means to draw a diagram which would be the best way to show you how to solve given problem so I will give it a try with words. \n" ); document.write( ".. \n" ); document.write( "If you draw the given headings correctly you should get a triangle with sides of 205 and 160 and their included angle of 164º. The problem can then be solved with the Law of Cosines. \n" ); document.write( "let me describe what the diagram should look like: \n" ); document.write( "Starting from a point labeled A, travel a distance of 160 miles rotated 33º west of North. At the end of the 160 miles, labeled point B, travel a distance of 205 miles rotated 49º west of North at point B. Mark the end of 205 miles as point C. Connect point C to beginning point A to complete the triangle. You now have a triangle with sides 160 & 205 with their included angle CBA. You can notice that this obtuse angle is made up of the complement of 49º=41º, the parallel angle of 33º plus 90º for a total of 41+33+90=164º \n" ); document.write( "solution: Using Law of Cosines: c^2=a^2+b^2-2abCosC \n" ); document.write( "let x= side CA \n" ); document.write( "x^2=120^2+205^2-2*160*205*cos164º \n" ); document.write( "x^2=14400+42025+63059=119484 \n" ); document.write( "x=346 miles \n" ); document.write( "ans: \n" ); document.write( "The plane is 346 miles from its original position \n" ); document.write( " |