h is the flagpole
a is 20m
b is unknown distance along level ground to flagpole, from where 60 degree measure is taken
...
We have:
and
Solving each of these for h:
and
Solve for b by setting the above two equation equal:
...
Then from : or approx to two decimal places
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a = 20m from "...another point on the ground 20m nearer the flagpole,"
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Dear student, please read the entire problem statement carefully!
In the diagram below, I have added points "A" and "B" which are the two points where the angles are measured. If you start at "A" and walk to "B" (which is distance 'a'), you will have walked 20m. Point "B" is "20m nearer to the flagpole." This is stated clearly within the original problem statement.