document.write( "Question 145407: A ladder is leaning against a wall. The distance from the bottom of the ladder to the wall is 3 feet less than the length of the ladder. Find the length of the ladder, if the distance of its top to the ground is 4 feet less than the length of the ladder. \n" ); document.write( "
Algebra.Com's Answer #106086 by ankor@dixie-net.com(22740)\"\" \"About 
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A ladder is leaning against a wall. The distance from the bottom of the ladder to the wall is 3 feet less than the length of the ladder. Find the length of the ladder, if the distance of its top to the ground is 4 feet less than the length of the ladder.
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\n" ); document.write( "Using the formula a^2 + b^2 = c^2
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\n" ); document.write( "Let x = length of the ladder (c)
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\n" ); document.write( "\"The distance from the bottom of the ladder to the wall is 3 feet less than the length of the ladder.\" Therefore:
\n" ); document.write( "(x-3) = a
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\n" ); document.write( "\"the distance of its top to the ground is 4 feet less than the length of the ladder.\" therefore:
\n" ); document.write( "(x-4) = b
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\n" ); document.write( "Using the formula we have:
\n" ); document.write( "(x-3)^2 + (x-4)^2 = x^2
\n" ); document.write( "FOIL
\n" ); document.write( "(x^2 - 6x + 9) + (x^2 - 8x + 16) = x^2
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\n" ); document.write( "Combine like terms on the left
\n" ); document.write( "x^2 + x^2 - x^2 - 6x - 8x + 9 + 16 = 0
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\n" ); document.write( "x^2 - 14x + 25 = 0
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\n" ); document.write( "Solve for x using the quadratic formula;
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( " a=1; b=-14; c=25
\n" ); document.write( "\"x+=+%28-%28-14%29+%2B-+sqrt%28-14%5E2+-+4+%2A+1+%2A+25+%29%29%2F%282%2A1%29+\"
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\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28196+-+100+%29%29%2F%282%29+\"
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\n" ); document.write( "you can do the math here, the reasonable solution is x = 11.9' length of ladder
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\n" ); document.write( "Check solution
\n" ); document.write( "8.9^2 + 7.9^2 = 141.6 which is 11.9 squared\r
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