document.write( "Question 686696: I am not understanding how to start this word problem. We are supposed to be using quadratic equations. The problem is.....
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\n" ); document.write( " The length of a rectangle is 1cm more than twice it's width and 2cm less than the length of the diagonal of the rectangle. Find the dimensions of the rectangle.\r
\n" ); document.write( "\n" ); document.write( "I think the diagonal part is confusing me because we have never solved a problem with diagonal before.
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Algebra.Com's Answer #424890 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
The length of a rectangle is 1cm more than twice it's width and 2cm less than the length of the diagonal of the rectangle.
\n" ); document.write( " Find the dimensions of the rectangle.
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\n" ); document.write( "Let a = the width
\n" ); document.write( "Let b = the length
\n" ); document.write( "Let c = the diagonal
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\n" ); document.write( "Write an equation for each statement, get each equation in terms of a:
\n" ); document.write( "\"The length of a rectangle is 1cm more than twice it's width\"
\n" ); document.write( "b = 2a + 1
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\n" ); document.write( "\"the length is 2cm less than the length of the diagonal of the rectangle.\"
\n" ); document.write( "b = c - 2
\n" ); document.write( "replace b with (2a+1)
\n" ); document.write( "2a + 1 = c - 2
\n" ); document.write( "2a + 1 + 2 = c
\n" ); document.write( "c = 2a + 3
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\n" ); document.write( "The diagonal is the hypotenuse (c) of the rectangle where
\n" ); document.write( "a^2 + b^2 = c^2
\n" ); document.write( "Replace b with (2a+1) and replace c with (2a+3)
\n" ); document.write( "a^2 + (2a+1)^2 = (2a+3)^2
\n" ); document.write( "FOIL
\n" ); document.write( "a^2 + 4a^2 + 2a + 2a + 1 = 4a^2 + 6a + 6a + 9
\n" ); document.write( "Which is
\n" ); document.write( "5a^2 + 4a + 1 = 4a^2 + 12a + 9
\n" ); document.write( "Combine like terms on the left
\n" ); document.write( "5a^2 - 4a^2 + 4a - 12a + 1 - 9 = 0
\n" ); document.write( "a^2 - 8a - 8 = 0
\n" ); document.write( "Solve this quadratic equation using the quadratic formula
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "where x = a; b = -8; c = -8
\n" ); document.write( "\"a+=+%28-%28-8%29+%2B-+sqrt%28-8%5E2-4%2A1%2A-8+%29%29%2F%282%2A1%29+\"
\n" ); document.write( "\"a+=+%288+%2B-+sqrt%2864%2B32+%29%29%2F2+\"
\n" ); document.write( "\"a+=+%288+%2B-+sqrt%2896%29%29%2F2+\"
\n" ); document.write( "two solutions but we only need the positive solution which is approx
\n" ); document.write( "a = \"%288+%2B+9.8%29%2F2\"
\n" ); document.write( "a = \"17.8%2F2\"
\n" ); document.write( "a = 8.9 cm is the width
\n" ); document.write( "then
\n" ); document.write( "b = 2(8.9) + 1
\n" ); document.write( "b = 18.8 cm is the length
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\n" ); document.write( "Check this by finding the hypotenuse
\n" ); document.write( "c = 2(8.9) + 3
\n" ); document.write( "c = 20.8
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\n" ); document.write( "Enter into calc \"sqrt%288.9%5E2+%2B+18.8%5E2%29\" results: 20.800 confirms our solution
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\n" ); document.write( " Find the dimensions of the rectangle. 18.8 by 8.9
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