document.write( "Question 167320: I have the total surface area, and I have two of the three dimensions given, how do I figure out the missing (third) dimension? \n" ); document.write( "

Algebra.Com's Answer #123245 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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I have the total surface area, and I have two of the three dimensions given, how do I figure out the missing (third) dimension?
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\n" ); document.write( "Look at the Surface area equation:
\n" ); document.write( "Dimensions: L by W by H
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\n" ); document.write( " 2LW + 2LH + 2WH = SA
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\n" ); document.write( "Let's say the missing dimension is L. Solve this equation for L
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\n" ); document.write( "Subtract 2WH from both sides:
\n" ); document.write( "2LW + 2LH = SA - 2WH
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\n" ); document.write( "Factor out L on the left
\n" ); document.write( "L(2W + 2H) = SA - 2WH
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\n" ); document.write( "Divide both side by (2W+2H) and you have:
\n" ); document.write( "L = $\"%28%28SA-2WH%29%29%2F%28%282W%2B2H%29%29\"$
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\n" ); document.write( "Substitute the other two dimensions (W & H) and the surface area to find L \n" ); document.write( "

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