document.write( "Question 695021: The volume of a rectangular solid is 540 cubit feet. The width is 3 feet more than the height, and the lenght is 4 more feet than the height. Find the dimensions of the solid.
\n" ); document.write( "w=h+3
\n" ); document.write( "l=h+4
\n" ); document.write( "h= ?
\n" ); document.write( "540=(h+3)*(h+4)*h
\n" ); document.write( "540=h^3+7h^2+12h
\n" ); document.write( "How to resolve ?
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Algebra.Com's Answer #428320 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
\"540=h%5E3%2B7h%5E2%2B12h\" --> \"h%5E3%2B7h%5E2%2B12h-540=0\"
\n" ); document.write( "Any rational zero of the polynomial \"P%28h%29=h%5E3%2B7h%5E2%2B12h-540\" will be a factor of \"540\", with a + or a - sign.
\n" ); document.write( "\"540=2%5E2%2A3%5E3%2A5\"
\n" ); document.write( "You know we are looking for a positive solution, so I would try + signs first.
\n" ); document.write( "The choices for factors are 1,2,3,4,5,6,9,10,12,15,18,20,27,30,36,45,54,60,90,108,135,180,270, and 540.
\n" ); document.write( "It is obvious that for positive \"h\" values, as \"h\" increases, \"P%28h%29\" increases.
\n" ); document.write( "\"P%281%29=1%2B7%2B12-540%3C0\" and \"P%2810%29=1000%2B700%2B120-540%3E0\",
\n" ); document.write( "so the solution could be one of the factors in between 1 and 10: 2,3,4,5,6,and 9.
\n" ); document.write( "\"P%285%29=125%2B7%2A25%2B12%2A5-540=125%2B175%2B60-540=360-540=-180\",
\n" ); document.write( "so we expect that the solution could be one of the factors between 5 and 10 (either 6 or 9).
\n" ); document.write( "\"P%286%29=216%2B7%2A36%2B12%2A6-540=216%2B252%2B72-540=0\", so \"highlight%28h=6%29\" is one solution.
\n" ); document.write( "Is there another solution?
\n" ); document.write( "Of course not.
\n" ); document.write( "If we make \"h\" smaller, the width and length will be smaller, and the volume will have to be smaller.
\n" ); document.write( "If we make \"h\" larger, the width and length will be larger, and the volume will have to be larger.
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