document.write( "Question 159731: Find the dimensions of a rectangle whose perimeter is 26 meters and whose area is 40 square meters. \n" ); document.write( "
Algebra.Com's Answer #117769 by KnightOwlTutor(293)\"\" \"About 
You can put this solution on YOUR website!
We know that the perimeter is equal to the length of all the sides
\n" ); document.write( "X=width
\n" ); document.write( "Y=length\r
\n" ); document.write( "\n" ); document.write( "The perimeter of the rectangle=X+X+Y+Y=26\r
\n" ); document.write( "\n" ); document.write( "Simplify to 2X+2Y=26\r
\n" ); document.write( "\n" ); document.write( "we know that the area is the width multplied by the length
\n" ); document.write( "XY=40
\n" ); document.write( "We isolate X by dividing Y on both sides X=40/Y\r
\n" ); document.write( "\n" ); document.write( "Replace 40/Y for X in the perimeter equation\r
\n" ); document.write( "\n" ); document.write( "2(40/Y) +2Y=26\r
\n" ); document.write( "\n" ); document.write( "Multiply each term on both sides by Y\r
\n" ); document.write( "\n" ); document.write( "80+2Y^2=26Y\r
\n" ); document.write( "\n" ); document.write( "subtract 26Y from both sides\r
\n" ); document.write( "\n" ); document.write( "80-26Y+2Y^2=0\r
\n" ); document.write( "\n" ); document.write( "This is a quadratic equation
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Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B-26x%2B80+=+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=%28-26%29%5E2-4%2A2%2A80=36\".
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\n" ); document.write( " Discriminant d=36 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--26%2B-sqrt%28+36+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-26%29%2Bsqrt%28+36+%29%29%2F2%5C2+=+8\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-26%29-sqrt%28+36+%29%29%2F2%5C2+=+5\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B-26x%2B80\" can be factored:
\n" ); document.write( " \"2x%5E2%2B-26x%2B80+=+%28x-8%29%2A%28x-5%29\"
\n" ); document.write( " Again, the answer is: 8, 5.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-26%2Ax%2B80+%29\"

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