Question
Find the height of a tree when it is found that on walking away from it 20 metres, in horizontal line through its base, the elevation of its top changes from 60 degree to 30 degree.
Answers
drwls
Let the height be H.
Let the (closer) distance for which the elevation is 60 degrees be D.
H/D = tan 60 = sqrt3 = 1.732
H/(D+20) = tan30 = 1/sqrt3= 0.5774
(D+20)/D = 3
1 + 20/D = 3
20/D = 2
D = 10 m, exactly
H = sqrt3*10 = 17.32 m
Let the (closer) distance for which the elevation is 60 degrees be D.
H/D = tan 60 = sqrt3 = 1.732
H/(D+20) = tan30 = 1/sqrt3= 0.5774
(D+20)/D = 3
1 + 20/D = 3
20/D = 2
D = 10 m, exactly
H = sqrt3*10 = 17.32 m
Prateeksha
Can u please do the sum much clearly