The angle of elevation to the top of a tower from point a on the ground is 18.6 degrees . from a point b, 39.3 feet closer to the tower, the angle of elevation is 21.4 degrees . what is the height of the tower
Accepted Solution
A:
this description would make two triangles on the same side of a pole.
to find one of the other angles in the triangle, (the one between the ground and angle b)
180 - 21.4 = 158.6
the third angle would then be 180 - 158.6 - 18.6 = 140
you could then use the sine law to solve for the hypotenuse
c/158.6 = 39.3/140 140x = 6232.98 c = 6232.98/140 c = 44.5
then you would need to solve for the hypotenuse of the right angle triangle
c/18.6 = 44.5/158.6 158.6c = 827.7 c = 827.7/158.6 c = 5.2
then you can use sin21.4 = a/5.2 to solve for the height of the tower