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The top of a 16-foot ladder is 2 feet farther up a wall than the foot is from the bottom of the wall. How far is the ladder from the bottom of the wall?

User Nickspiel
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1 Answer

6 votes
Let x=distance of foot of ladder from the wall, then
x+2=height of top of ladder up the wall.
length of ladder = 16 feet.
Using Pythagoras theorem,
x^2+(x+2)^2=16^2, expand and simplify
2x^2+4x+4 = 256 again simplify
x^2+2x-126=0 [fail to factor]
apply quadratic equation:
x=(-2+/-sqrt(4+504))/2
=-1+/-sqrt(127)
x=-12.3 (rejected) or
x=10.27 feet from wall.
User Munjal
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