A pole is ﬁxed vertically on a plane. An ant while walking on the plane, observes that
its angle of elevation to the top of the pole is 45 degrees. Then it walks 1 m straight towards
the pole, turns left and then moves 2 m further. If it ﬁnds the angle of elevation is again 45 degrees, then the height of the pole is
a) 2.5 m
b) 2 m
c) root 2 m
d) (root 3)/2 m

Question

A pole is ﬁxed vertically on a plane. An ant while walking on the plane, observes that
its angle of elevation to the top of the pole is 45 degrees. Then it walks 1 m straight towards
the pole, turns left and then moves 2 m further. If it ﬁnds the angle of elevation is again 45 degrees, then  the height of the pole is
a) 2.5 m
b) 2 m
c) root 2 m
d) (root 3)/2 m

anonymous · Answer

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Therefore
x^2 = (x-1)^2 + 2^2
4 = x + x - 1 
Therefore x = 5/2