document.write( "Question 184287: The length of a rectangular frame is 7cm more than the width. The area inside the the frame is 98 square cm. Find the width of the frame. \n" ); document.write( "
Algebra.Com's Answer #138309 by MathGuyJoe(20)\"\" \"About 
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Let L = Length of rectangle
\n" ); document.write( "Let W = Width of rectangle
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\n" ); document.write( "We know: \"The length of a rectangular frame (L) is (=) 7cm more than (+) the width (W)\" -> Equation 1: \"+L+=+7+%2B+W+\"\r
\n" ); document.write( "\n" ); document.write( "We also know: \"The area inside the frame (L x W) is (=) 98 square cm\" -> Equation 2: \"+LW+=+98+\"
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\n" ); document.write( "Next, we can use Equation 1 to substitute (7 + W) for L in Equation 2:
\n" ); document.write( "\"+LW+=+98+\"
\n" ); document.write( "Substitute:
\n" ); document.write( "\"+%287%2BW%29W+=+98+\"
\n" ); document.write( "Distribute the W:
\n" ); document.write( "\"+7W+%2B+W%5E2+=+98+\"
\n" ); document.write( "Move everything to the left-hand side:
\n" ); document.write( "\"+W%5E2+%2B+7W+-+98+=+0+\"
\n" ); document.write( "Factor the quadratic:
\n" ); document.write( "\"+%28W+%2B+14%29%28W+-+7%29+=+0+\"
\n" ); document.write( "Solve:
\n" ); document.write( "\"W+%2B+14+=+0\" \"W-7=+0\"
\n" ); document.write( "\"W+=+-14\" \"W+=+7\"
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\n" ); document.write( "Since a width cannot be negative, that leaves us with Width = 7cm.
\n" ); document.write( "To check our answer, calculate our length by substituting back into Equation 1:
\n" ); document.write( "\"+L+=+W+%2B+7+\"
\n" ); document.write( "\"+L+=+7+%2B+7+\"
\n" ); document.write( "\"+L+=+14+\"
\n" ); document.write( "Next, ensure the area is 98 square cm:
\n" ); document.write( "\"+LW+=+98+\"
\n" ); document.write( "\"+%2814%29%287%29+=+98+\"
\n" ); document.write( "\"+98+=+98+\"
\n" ); document.write( "

\n" ); document.write( "Hope this helps. ~ Joe
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