Q14 of 56 Page 6

The foot of a ladder is 6 m away from a wall and its top reaches a window 8 m above the ground. If the ladder is shifted in such a way that its foot is 8 m away from the wall, to what height does its tip reach?

Given: AB = 8 m


CD = 6 m


To find: Height to the tip reaches


Theorem Used:


Pythagoras theorem:


In a right-angled triangle, the squares of the hypotenuse is equal to the sum of the squares of the other two sides.


Explanation:



Let length of ladder be AD = BE = t m


InACD


AD2=AC2+CD2


t2= 82+62 ……. (i)


In BCE


BE2=BC2+EC2


t2= BC2+82 …… (ii)


From (i) and (ii)


BC2+82=82+62


BC2=62


BC=6m


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