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The base of 40-foot ladder is 8 feet from the wall. How high is the ladder on the wall (round to the nearest foot)

User Eos
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1 Answer

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Given:

The base of 40-foot ladder is 8 feet from the wall.

To find:

How high is the ladder on the wall (round to the nearest foot).

Solution:

Ladder makes a right angle triangle with wall and ground.

We have,

Length of ladder (hypotenuse)= 40 foot

Base = 8 foot

We need to find the perpendicular to get the height of the ladder on the wall.

Let h be the height of the ladder on the wall.

According to the Pythagoras theorem,


Hypotenuse^2=Base^2+Perpendicular^2


(40)^2=(8)^2+(h)^2


1600=64+h^2


1600-64=h^2


1536=h^2

Taking square root on both sides.


\pm √(1536)=h


\pm 39.1918358=h

Height cannot be negative. Round to the nearest foot.


h\approx 39

Therefore, the height of the ladder on the wall is 39 foot.