A surveyor has determined that a mountain is h = 2470 ft high. From the top of the mountain he measures the angles of depression to two landmarks at the base of the mountain and finds them to be 42° and c = 38°. The angle between the lines of sight to the landmarks is 68°. Calculate the distance between the two landmarks.
This is an image that is with the problem and these words were included in the description: (Observe that these are the same as the angles of elevation from the landmarks as shown in the figure below.)
look at the third triangle and find two sides of it using the height and the angles provided
Using these:\[\frac{ 2470 }{ \sin38 }=\frac{ x }{\sin52}\] x=3161.4 \[\frac{ 2470 }{ \sin42 }=\frac{ x }{\sin16}\] x=1017.5 Then I found the angle in between to be 148. Then using law of cosines I did:\[a^2 = 3161.4^2 + 1017.5^2 - 2(3161.4)(1017.5)\cos(148)\] This resulted in a= 4060 (I only needed it as an integer) This answer was incorrect. Where did I go wrong?
sin 32=.... sin 42=....
you could then find the two sides of the angle 68 and then use the cos law
I think I must not be following. I still got 4060.2 =/
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