document.write( "Question 189460: At a point on the ground 35 ft from the base of a tree, the distance to the top of the tree is 1 ft more than 3 times height of the tree. Find the height of the tree. \n" ); document.write( "
Algebra.Com's Answer #142133 by nerdybill(7384)\"\" \"About 
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At a point on the ground 35 ft from the base of a tree, the distance to the top of the tree is 1 ft more than 3 times height of the tree. Find the height of the tree.
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\n" ); document.write( "Drawing a diagram of the problem will help you \"see\" the solution.
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\n" ); document.write( "You will be applying the Pythagorean theorem.
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\n" ); document.write( "Let h = height of the tree
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\n" ); document.write( "3h+1 is the hypotenuse
\n" ); document.write( "the other two sides are:
\n" ); document.write( "h and 35
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\n" ); document.write( "h^2 + 35^2 = (3h+1)^2
\n" ); document.write( "h^2 + 35^2 = (3h+1)(3h+1)
\n" ); document.write( "h^2 + 35^2 = 9h^2 + 6h + 1
\n" ); document.write( "35^2 = 8h^2 + 6h + 1
\n" ); document.write( "1225 = 8h^2 + 6h + 1
\n" ); document.write( "0 = 8h^2 + 6h - 1224
\n" ); document.write( "0 = 4h^2 + 3h - 612
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\n" ); document.write( "Applying the quadratic formula gives us:
\n" ); document.write( "h = {12, -12.75}
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\n" ); document.write( "Toss out the negative solution leaves us with:
\n" ); document.write( "h = 12 feet (height of tree)
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\n" ); document.write( "Details of quadratic follows:
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ah%5E2%2Bbh%2Bc=0\" (in our case \"4h%5E2%2B3h%2B-612+=+0\") has the following solutons:
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\n" ); document.write( " \"h%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%283%29%5E2-4%2A4%2A-612=9801\".
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\n" ); document.write( " Discriminant d=9801 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-3%2B-sqrt%28+9801+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"h%5B1%5D+=+%28-%283%29%2Bsqrt%28+9801+%29%29%2F2%5C4+=+12\"
\n" ); document.write( " \"h%5B2%5D+=+%28-%283%29-sqrt%28+9801+%29%29%2F2%5C4+=+-12.75\"
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\n" ); document.write( " Quadratic expression \"4h%5E2%2B3h%2B-612\" can be factored:
\n" ); document.write( " \"4h%5E2%2B3h%2B-612+=+4%28h-12%29%2A%28h--12.75%29\"
\n" ); document.write( " Again, the answer is: 12, -12.75.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+4%2Ax%5E2%2B3%2Ax%2B-612+%29\"

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