document.write( "Question 54870: I could really use some help with this problem. Thanks! The area of a rectangle is 45 square cm. If the length is 4 cm greater than the width, what are the dimension of the rectangle? \n" ); document.write( "
Algebra.Com's Answer #37170 by ankor@dixie-net.com(22740)\"\" \"About 
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The area of a rectangle is 45 square cm. If the length is 4 cm greater than the width, what are the dimension of the rectangle?
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\n" ); document.write( "Write an equation which translates the following sentence:
\n" ); document.write( "\"the length is 4 cm greater than the width,\" (the word \"is\" usually means \"=\")
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\n" ); document.write( " L = W + 4
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\n" ); document.write( "We know that:
\n" ); document.write( " L * W = 45 sq cm
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\n" ); document.write( "Substitute (W + 4) for L, and you have:
\n" ); document.write( "(W+4) * W = 45
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\n" ); document.write( "W^2 + 4W = 45
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\n" ); document.write( "W^2 + 4W - 45 = 0; our old friend the quadratic equation
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\n" ); document.write( "Factors easily to:
\n" ); document.write( "(W + 9) (W - 5) = 0
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\n" ); document.write( "W = -9
\n" ); document.write( "and
\n" ); document.write( "W = +5, the positive solution is what we want in the real world
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\n" ); document.write( "L = 5 + 4 = 9: Checks out: 9 * 5 = 45\r
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