If the height of a tower and the distance of the point of observation from its foot, both are increased by 10%, then the angle of elevation of its top remains unchanged.

True

Let height of the tower be h and distance of the point from its foot is x.

Let angle of elevation be θ_{1}

In

…eq. 1

Now, when both(height and distance) are increased by we get

New height = h+10%of h

New distance = x+10% of x

In ∆PQR,

From eq.1 and eq.2, we get θ_{1} = θ_{2}

Hence, it is true.

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