SOLUTION: A ladder 20 feet long is leaning against a wall and reaches the top of the wall. If the height of the wall is 4 feet more than the distance between the foot of the ladder and the

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: A ladder 20 feet long is leaning against a wall and reaches the top of the wall. If the height of the wall is 4 feet more than the distance between the foot of the ladder and the       Log On


   



Question 674814: A ladder 20 feet long is leaning against a wall and reaches the top of the wall. If the height of the wall is 4 feet more than the distance between the foot of the ladder and the base of the wall, find the height of the wall.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A ladder 20 feet long is leaning against a wall and reaches the top of the wall. If the height of the wall is 4 feet more than the distance between the foot of the ladder and the base of the wall, find the height of the wall.
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Draw picture of the right triangle formed.
hypotenuse = length of ladder = 20 ft
base of the triangle = x
height = x + 4
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Equation:
x^2 + (x+4)^2 = 20^2
2x^2 + 8x + 16 = 400
x^2 + 4x - 192 = 0
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Solve using the Quadratic Formula:
Cheers,
Stan H.