document.write( "Question 1197235: Is it possible to have a rectangular property which has perimeter of 78 m and an area of 395m^2? \n" ); document.write( "
Algebra.Com's Answer #830427 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "L = length
\n" ); document.write( "W = width\r
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\n" ); document.write( "\n" ); document.write( "P = perimeter of a rectangle
\n" ); document.write( "P = 2(L+W) = 2L+2W\r
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\n" ); document.write( "\n" ); document.write( "Replace P with the stated perimeter 78 and let's isolate L
\n" ); document.write( "P = 2L+2W
\n" ); document.write( "78 = 2L+2W
\n" ); document.write( "78/2 = 2L/2+2W/2
\n" ); document.write( "39 = L+W
\n" ); document.write( "L = 39-W\r
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\n" ); document.write( "\n" ); document.write( "A = area of a rectangle
\n" ); document.write( "A = LW
\n" ); document.write( "A = (39-W)W
\n" ); document.write( "A = -W^2+39W\r
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\n" ); document.write( "\n" ); document.write( "Plug in the stated area A = 395
\n" ); document.write( "I'll replace each W with x
\n" ); document.write( "A = -W^2+39W
\n" ); document.write( "395 = -x^2+39x
\n" ); document.write( "395+x^2-39x = 0
\n" ); document.write( "x^2-39x+395 = 0\r
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\n" ); document.write( "\n" ); document.write( "Use the quadratic formula to solve for x.
\n" ); document.write( "Use a = 1, b = -39, c = 395.
\n" ); document.write( "\"x+=+%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%28-39%29%2B-sqrt%28%28-39%29%5E2-4%281%29%28395%29%29%29%2F%282%281%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2839%2B-sqrt%281521-1580%29%29%2F%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2839%2B-sqrt%28-59%29%29%2F%282%29\"
\n" ); document.write( "The discriminant \"d+=+b%5E2+-+4ac+=+%28-39%29%5E2-4%281%29%28395%29+=+-59\" is negative, so there are no real number solutions.
\n" ); document.write( "The two roots of x^2-39x+395 = 0 are complex numbers in the form a+bi where \"i+=+sqrt%28-1%29\"
\n" ); document.write( "If your teacher hasn't covered complex or imaginary numbers just yet, then ignore this subsection.
\n" ); document.write( "The summary is that x^2-39x+395 = 0 has no real solutions.\r
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\n" ); document.write( "\n" ); document.write( "Since x^2-39x+395 = 0 has no real solutions, this means we cannot have a rectangle with perimeter 78 meters and area 395 square meters.
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