D.r Black is standing 20 feet from a streetlamp. The lamp is making his shadow 5 feet long. He estimates that the angle of elevation from the tip of his shadow to the top of the streetlamp is 30°. How tall is the street lamp to the nearest foot?

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Answer 1 · 2017-10-10T14:04:02

Explained:

Length of shadow= 5 feet
Distance between him and lamp= 20 feet
Total distance = 25 feet
Angle of elevation = 30 degrees

tan 30 = height of lamp/total distance
#1/sqrt 3#= height of lamp / 25

#25/sqrt3#= height of lamp
#25/1.732#= height of lamp
Height of lamp = 14.43 feet.