Two poles of heights 6 m and 11 m stand on a plane ground. If the distance between the feet of the poles is 12 m, find the distance between their tops

Solution:

We know that in a right triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides. 

AB is the height of one pole = 6m

CD is the height of another pole = 11m

AC is the distance between two poles at bottom = 12m

BD is the distance between the tops of the poles = ?

Draw BE || AC

Now consider, in Δ BED

∠BED = 90°

BE = AC = 12 m

DE = CD - CE

DE = 11 - 6 = 5 cm

Now, 

BD² = BE² + DE²  (Pythagoras therorem)

BD² = 12² + 5²

BD² = 144 + 25

BD² = 169

BD = 13m

The distance between the top of the poles is 13 m.

☛ Check: NCERT Solutions for Class 10 Maths Chapter 6

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Video Solution:

Two poles of heights 6 m and 11 m stand on a plane ground. If the distance between the feet of the poles is 12 m, find the distance between their tops.
 

NCERT Class 10 Maths Solutions Chapter 6 Exercise 6.5 Question 12

Summary:

Two poles of heights 6 m and 11 m stand on a plane ground. If the distance between the feet of the poles is 12 m, then the distance between their tops is 13 m.

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