Question 1185051
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A ladder is 25 {{{cross(cm)}}} <U>meters</U> long leans against a vertical wall so that the base of the ladder
is 7 m from the foot of the wall. If the top of the ladder slides 4 m down the wall,
by how many meters will the base of the ladder move away from the foot of the wall?
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<pre>
In this problem, you have two right angled triangles, both with the hypotenuse of 25 meters, 
which represents the ladder.


In the first ladder's position, horizontal leg is 7 meters; hence, vertical leg is

    {{{sqrt(25^2-7^2)}}} = {{{sqrt(576)}}} = 24 meters long.



When the ladder changes his position, sliding vertically  4 meters down, new vertical leg is 24 - 4 = 20 meters long.


Hence, new horizontal leg is  {{{sqrt(25^2 - 20^2)}}} = {{{sqrt(225)}}} = 15 meters long.


It is the new position of the base of the ladder.


So, we just solved the problem and obtained the <U>ANSWER</U>: the base of the ladder will move by 15 - 7 = 8 meters.
</pre>

Solved.