document.write( "Question 889337: A rectangle is 72 sq.m and its perimeter is 34 m.find its length and breadth? \n" ); document.write( "
Algebra.Com's Answer #538092 by LinnW(1048)\"\" \"About 
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set W = width
\n" ); document.write( "set L = length
\n" ); document.write( "L*W = 72
\n" ); document.write( "2W + 2L = 34
\n" ); document.write( "add -2L to each side
\n" ); document.write( "2W = 34 - 2L
\n" ); document.write( "divide each side by 2
\n" ); document.write( " W = 17 - L
\n" ); document.write( "substitute ( 17 - L ) for W in L*W = 72
\n" ); document.write( "L*( 17 - L ) = 72
\n" ); document.write( "17L - L^2 = 72
\n" ); document.write( "add -72 to each side
\n" ); document.write( "17L - L^2 - 72 = 0
\n" ); document.write( "multiply each side by -1
\n" ); document.write( "L^2 - 17L + 72 = 0
\n" ); document.write( "(L - 8)(L - 9) = 0
\n" ); document.write( "So L = 8 or L = 9
\n" ); document.write( "Suppose L = 9
\n" ); document.write( "Substitute 9 for L in 2W + 2L = 34
\n" ); document.write( " 2W + 2(9) = 34
\n" ); document.write( " 2W + 18 = 34
\n" ); document.write( "add -18 to each side
\n" ); document.write( " 2W = 16
\n" ); document.write( " W = 8
\n" ); document.write( "So length is 9 and width is 8
\n" ); document.write( "
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