document.write( "Question 991004: The length of a rectangle is 3 times the width. The area is 108 cm^2. Find the dimensions of the rectangle. \n" ); document.write( "

Algebra.Com's Answer #610925 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "Let x be the length in centimeters, and y be the width in centimeters.\r
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\n" ); document.write( "\n" ); document.write( "You have two equations\r
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\n" ); document.write( "\n" ); document.write( " $\"system%28x+=+3y%2C%0D%0Axy+=+108%29\"$ .\r
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\n" ); document.write( "\n" ); document.write( "Substitute the expression for x from the first equation to the second one. You will get\r
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\n" ); document.write( "\n" ); document.write( " $\"3y%5E2\"$ = $\"108\"$ ,\r
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\n" ); document.write( "\n" ); document.write( " $\"y%5E2\"$ = $\"108%2F3\"$ = 36,\r
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\n" ); document.write( "\n" ); document.write( "y = +/- 6.\r
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\n" ); document.write( "\n" ); document.write( "Only positive value suits. Thus the width is 6 cm.\r
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\n" ); document.write( "\n" ); document.write( "Hence, the length is 3*6 = 18 cm.\r
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\n" ); document.write( "\n" ); document.write( "Check. 18*6 = 108 $\"cm%5E2\"$ . \r
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