I’ve tried so many times and can’t get it
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Answer:
Set your calculator to degree mode.
tan(61°) = AB/21
AB = 21tan(61°)
Let x = the length of the telephone pole.
cos(8°) = 21tan(61°)/x
x•cos(8°) = 21tan(61°)
x = 21tan(61°)/cos(8°) = about 38 feet
38 goes into the box.