<PRE><B>Question 184290</B>
Let x = distance from the wall
x+3 = length of the ladder


By Theorem of Pythagoras:
{{{x^2+ 9^2 = (x+3)^2}}}

{{{x^2 + 81 = x^2 + 6x + 9}}}


Subtract x^2 from each side:
81=6x+9
72 = 6x
x= 12 feet  = distance from wall
x+3 = 15 feet  = length of the ladder


Check:  
{{{ 12^2 + 9^2 = 15^2 }}}
{{{144+81= 225}}}


R^2

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