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Q: A 5 foot ladder is leaning against a 4 foot wall How many feet above the ground does the ladder touch the wall?

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Using Pythagoras' theorem the length of the base is 7 feet

1 metres

It can mean the height from the ground to the roof peak, or the ground elevation above or below sea level.

Pie times the radius squared

It depends on how heigh the window sill is from the ground. it can be right above it, or far from the floor.

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12

12 feet.

Use Pythagoras' theorem: 152-92 = 144 and the square root of 144 is 12 Answer: 12 feet

12 feet. It is actually pretty easy, if you remember that a 3x4x5 triangle is always a right angle. divide by 3 and you have the 3 and 5 all you need is the four multiplied by 3.

This answer uses trigonometry to avoid a lot of work:tangent = opposite/adjacent and tangent*adjacent (base of ladder from the building) = opposite (height of ladder above ground)So: tangent 60 degrees*3 = 5.196152423Therefore: Top of the ladder above ground = 5.2 meters correct to one decimal place.More laborious methodThe right triangle formed by the wall, ground and ladder has sides in the ratio of 1::2::sq-rt-of-3. The shortest side is the one opposite the 30 degree angle, i.e., the given distance from wall to base of the ladder--3 m.The length of the ladder represents the hypotenuse of the triangle, and is twice as long, hence 6 m.And the height of the ladder's top from the ground is proportional to the third side whose length is sq-rt-3 times that of the shortest side. Sq-rt-3 is about 1.732, so height of the ladder's top at the wall is about 5.20 m, or 520 cm.

For the ladder with the length of 8m 8.37m from the wall For the ladder with the length of 10m 10.44m from the wall

Using Pythagoras' theorem the length of the base is 7 feet

If it is an above ground yes

The ladder forms a right angle with the building: the ground and the building forming the right angle and the ladder forming the hypotenuse. If the length of the ladder is L metres, then sin(49) = 12/L So L = 12/sin(49) = 15.9 = 16 metres.

12 feet

so long as they don't move they should not be a problem.

If you take the trouble to draw a sketch of the situation that you've described, the method of solution, as well as the answer, will jump out at you. The ground, the wall, and the ladder, form a right triangle. The base is 9-ft, and the hypotenuse is 15-ft. If you've been assigned this problem as homework, then you've sat through enough geometry in class to know how to work with the right triangle. The length of the missing side is 12-ft, and it makes no difference how high the wall is, as long as it's high enough to support the upper end of the ladder.