Question

Two vertical poles of height 9m and 14m stand on a plane ground. If the distance between their feet is 12m, find the distance between their tops. 

Answer 1

Let the two poles be DE and AB and the distance between their bases be BE.
We have: 

DE = 9 m, AB = 14 m and BE = 12 m
Draw a line parallel to BE from D, meeting AB at C.
Then, DC = 12 m and AC = 5 m
We need to find AD, the distance between their tops. 

 

Applying Pythagoras theorem in right-angled ACD, we have:  

`AD^2=AC^2+DC^2` 

`AD^2=5^2+12^2=25+144=169` 

`AD=sqrt169=13m` 

Hence, the distance between the tops to the two poles is 13 m.