document.write( "Question 341864: The width of a rectangle is 8 less than twice its length. If the area of the rectangle is 200 cm^2, what is the length of the diagonal? \n" ); document.write( "
Algebra.Com's Answer #244812 by ankor@dixie-net.com(22740)\"\" \"About 
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The width of a rectangle is 8 less than twice its length.
\n" ); document.write( " If the area of the rectangle is 200 cm^2, what is the length of the diagonal?
\n" ); document.write( ":
\n" ); document.write( "Let x = the length
\n" ); document.write( "then
\n" ); document.write( "(2x-8) = the width
\n" ); document.write( "and
\n" ); document.write( "x(2x-8) = 200; the area
\n" ); document.write( "A quadratic equation
\n" ); document.write( "2x^2 - 8x - 200 = 0
\n" ); document.write( "Simplify, divide by 2
\n" ); document.write( "x^2 - 4x - 100 = 0
\n" ); document.write( "Find x 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( "In this equation: a=1; b=-4; c=-100
\n" ); document.write( "\"x+=+%28-%28-4%29+%2B-+sqrt%28-4%5E2-4%2A1%2A-100+%29%29%2F%282%2A1%29+\"
\n" ); document.write( ":
\n" ); document.write( "\"x+=+%284+%2B-+sqrt%2816+%2B+400+%29%29%2F2+\"
\n" ); document.write( ":
\n" ); document.write( "\"x+=+%284+%2B-+sqrt%28416+%29%29%2F2+\"
\n" ); document.write( "The positive solution is what we want here
\n" ); document.write( "\"x+=+%284+%2B+20.4%29%2F2+\"
\n" ); document.write( "x = \"24.4%2F2\"
\n" ); document.write( "x = 12.2 is the length
\n" ); document.write( "then
\n" ); document.write( "2(12.2) - 8 = 16.4 is the width
\n" ); document.write( ":
\n" ); document.write( "Check solution by finding the area: 12.2 * 16.4 = 200.1 ~ 200, close enough
\n" ); document.write( ":
\n" ); document.write( "Find the diagonal (d)
\n" ); document.write( "d = \"sqrt%2812.2%5E2+%2B+16.4%5E2%29\"
\n" ); document.write( "c = 20.44 cm is the diagonal
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