Question

28. Two poles of the height 15 m and 20 m stand vertically upright on a plane ground. If the distance between their feet is 12 m, find the distance between their tops. RRB NTPC (Phase I) 2016 (1) 11 m (2) 12 m (3) 13 m (4) 14 m

11th - 12th Class

Maths

Solution

172

4.0 (1 ratings)

28. (3) Given In ( Delta A B E, ) by pythagoras theorem, ( begin{aligned} therefore quad A B &=sqrt{B E^{2}+(A D-E D)^{2}} &=sqrt{(12)^{2}+(20-15)^{2}} &=sqrt{144+25} &=sqrt{169} &=13 mathrm{m} end{aligned} )