document.write( "Question 149714: Two square wire frames are to be constructed from a piece of wire 100 inches long. If the area enclosed by one frame is to be one-half the area enclosed by the other, find the dimensions of each frame. (Disregard the thickness of the wire.) \n" ); document.write( "
Algebra.Com's Answer #109839 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
Let x = side of smaller square
\n" ); document.write( "and y = side of larger square
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\n" ); document.write( "x^2 is the area of smaller square
\n" ); document.write( "y^2 is the area of larger square
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\n" ); document.write( "4x is the perimeter of smaller square
\n" ); document.write( "4y is the perimeter of larger square
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\n" ); document.write( "Since we have two unknowns, we need two equations:
\n" ); document.write( "From: \"Two square wire frames are to be constructed from a piece of wire 100 inches long.\" we get:
\n" ); document.write( "4x + 4y = 100
\n" ); document.write( "x + y = 25 (equation 1)
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\n" ); document.write( "From: \"If the area enclosed by one frame is to be one-half the area enclosed by the other\" we get:
\n" ); document.write( "x^2 = (1/2)y^2 (equation 2)
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\n" ); document.write( "solving equation 1 for x:
\n" ); document.write( "x + y = 25
\n" ); document.write( "x = 25 - y
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\n" ); document.write( "plug the above into equation 2 and solve for y:
\n" ); document.write( "x^2 = (1/2)y^2
\n" ); document.write( "(25-y)^2 = (1/2)y^2
\n" ); document.write( "625 - 50y + y^2 = (1/2)y^2
\n" ); document.write( "1250 - 100y + 2y^2 = y^2
\n" ); document.write( "1250 - 100y + y^2 = 0
\n" ); document.write( "y^2 - 100y + 1250 = 0
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\n" ); document.write( "From the \"quadratic equation\" you'll get:
\n" ); document.write( "y = 85.36
\n" ); document.write( "x = 14.64
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\n" ); document.write( "Therefore the dimensions are:
\n" ); document.write( "85.36 in by 85.36 in (larger square)
\n" ); document.write( "14.64 in by 14.64 in (smaller square)
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\n" ); document.write( "Details of the quadratic solution follows:
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ay%5E2%2Bby%2Bc=0\" (in our case \"1y%5E2%2B-100y%2B1250+=+0\") has the following solutons:
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\n" ); document.write( " \"y%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=%28-100%29%5E2-4%2A1%2A1250=5000\".
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\n" ); document.write( " Discriminant d=5000 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--100%2B-sqrt%28+5000+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"y%5B1%5D+=+%28-%28-100%29%2Bsqrt%28+5000+%29%29%2F2%5C1+=+85.3553390593274\"
\n" ); document.write( " \"y%5B2%5D+=+%28-%28-100%29-sqrt%28+5000+%29%29%2F2%5C1+=+14.6446609406726\"
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\n" ); document.write( " Quadratic expression \"1y%5E2%2B-100y%2B1250\" can be factored:
\n" ); document.write( " \"1y%5E2%2B-100y%2B1250+=+1%28y-85.3553390593274%29%2A%28y-14.6446609406726%29\"
\n" ); document.write( " Again, the answer is: 85.3553390593274, 14.6446609406726.\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-100%2Ax%2B1250+%29\"
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