document.write( "Question 706395: large plywood box has a volume of 768 ft3. Its length is 16 ft greater than its height, and its width is 4 ft less than its height. What are the dimensions of the box \n" ); document.write( "
Algebra.Com's Answer #435153 by ankor@dixie-net.com(22740)\"\" \"About 
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large plywood box has a volume of 768 ft3.
\n" ); document.write( "L * W * h = 768
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\n" ); document.write( " Its length is 16 ft greater than its height,
\n" ); document.write( "L = (h+16)
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\n" ); document.write( "and its width is 4 ft less than its height.
\n" ); document.write( "W = (h-4)
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\n" ); document.write( "(h+16)*(h-4)* h = 768
\n" ); document.write( "FOIL
\n" ); document.write( "(h^2 - 4h + 16h - 64) * h = 768
\n" ); document.write( "(h^2 + 12h - 64) * h = 768
\n" ); document.write( "h^3 + 12h^2 - 64h - 768 = 0
\n" ); document.write( "We can group factor this
\n" ); document.write( "h^2(h+12) - 64(h+12)
\n" ); document.write( "Factor out (h+12)
\n" ); document.write( "(h+12)(h^2-64) = 0
\n" ); document.write( "we are only interested in the positive solution
\n" ); document.write( "h^2 = 64
\n" ); document.write( "h = 8 ft is the height
\n" ); document.write( "then
\n" ); document.write( "L = 24, W = 4 ft
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\n" ); document.write( "Check: 24 * 4 * 8 = 768\r
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