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.

Step 1: According to the given measurements construct an image.
GIVEN: Two poles AD and CE of height 6 m, 11 m respectively.
Distance between the feet of two poles (DC) = 12 m
From the figure: AD = BC = 6 m
AB = DC = 12 m (Since, opposite sides of the rectangles are equal.)
It seems to be right angle triangle ABE
Step 2: Find the height of the right angle triangle
EXPLANATION: BE = CE - BC = 11- 6 = 5 m
Step 3: Use the Pythagoras formula to find the distance between the tops of the poles.
FORMULA: (hypotenuse)^2 = (side)^2 + (side)^2
EXAMPLE: AE^2 = AB^2 + BE^2
AE^2 = (12)^2 + (5)^2
AE^2 = 144 + 25
AE = \sqrt{169}
AE = 13 m
∴ AE = distance between the two tops of the poles = 13 m