SOLUTION: Two students ride on an helicopter to measure the
width of a lake. At a point 760 m above the lake, they are
able to measure using a lensatic sighting compass the angle of
depre
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-> SOLUTION: Two students ride on an helicopter to measure the
width of a lake. At a point 760 m above the lake, they are
able to measure using a lensatic sighting compass the angle of
depre
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Question 1194430: Two students ride on an helicopter to measure the
width of a lake. At a point 760 m above the lake, they are
able to measure using a lensatic sighting compass the angle of
depression on one side of the lake as 45° and the angle of
depression on the other side is 20°. What is the width of the lake? Found 3 solutions by josgarithmetic, ikleyn, Alan3354:Answer by josgarithmetic(39617) (Show Source):
In fact, think about the side with the 45 degree angle of depression. If you drew two connected right triangles then one length part along the bottom is 760 m, just as the height of the point above the lake.
Expression for lake width can then be .
You can put this solution on YOUR website! .
Two students ride on an helicopter to measure the
width of a lake. At a point 760 m above the lake, they are
able to measure using a lensatic sighting compass the angle of
depression on one side of the lake as 45° and the angle of
depression on the other side is 20°. What is the width of the lake?
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If the two observation points at the lake shore are on the different (opposite) sides from the helicopter,
then the lake width is
W = + = = 2848 m (rounded).
If the two observation points at the lake shore are on the same side from the helicopter,
then the lake width is
W = - = = 1328 m (rounded).
You can put this solution on YOUR website! Would be simpler and safer if they hovered over either shore.
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Would be a right triangle, and they wouldn't drown if the engine failed.
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