document.write( "Question 843443: Please help me to find the answer. Find the length of a side of an equilateral triangle whose altitude is 3 feet shorter than a side. \n" ); document.write( "
Algebra.Com's Answer #508213 by LinnW(1048)\"\" \"About 
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Set s = length of a side.
\n" ); document.write( "Bisecting one of the angles produces two triangles,
\n" ); document.write( "each with a base of (1/2)s. Since the height is 3
\n" ); document.write( "less than a side length, height = s - 3
\n" ); document.write( "By Pythagorean theorem
\n" ); document.write( "\"%28%281%2F2%29s%29%5E2+%2B+%28s+-+3%29%5E2+=+s%5E2\"
\n" ); document.write( "\"%281%2F4%29s%5E2+%2B+s%5E2+-6s+%2B9+=+s%5E2\"
\n" ); document.write( "\"%281%2F4%29s%5E2+%2B+s%5E2+-6s+%2B9+=+s%5E2\"
\n" ); document.write( "\"%285%2F4%29s%5E2+-6s+%2B9+=+s%5E2\"
\n" ); document.write( "multiply each side by 4
\n" ); document.write( "\"5s%5E2+-24s+%2B36+=+4s%5E2\"
\n" ); document.write( "subtract 4s^2 from each side
\n" ); document.write( "\"s%5E2+-24s+%2B36+=+0\"
\n" ); document.write( "There are two possible values for s.
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B-24x%2B36+=+0\") has the following solutons:
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\n" ); document.write( " \"x%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=%28-24%29%5E2-4%2A1%2A36=432\".
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\n" ); document.write( " Discriminant d=432 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--24%2B-sqrt%28+432+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-24%29%2Bsqrt%28+432+%29%29%2F2%5C1+=+22.3923048454133\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-24%29-sqrt%28+432+%29%29%2F2%5C1+=+1.60769515458674\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B-24x%2B36\" can be factored:
\n" ); document.write( " \"1x%5E2%2B-24x%2B36+=+1%28x-22.3923048454133%29%2A%28x-1.60769515458674%29\"
\n" ); document.write( " Again, the answer is: 22.3923048454133, 1.60769515458674.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-24%2Ax%2B36+%29\"
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