document.write( "Question 811373: An open box is made from a rectangular piece of cardboard whose length is twice the width, by cutting a 3 inch square from each corner and folding up the remaining sides. Find the dimensions of the box if the volume is 648 cubic inches \n" ); document.write( "
Algebra.Com's Answer #488711 by Cromlix(4381)\"\" \"About 
You can put this solution on YOUR website!
Width = x
\n" ); document.write( "Length = 2x
\n" ); document.write( "Cutting 3 inch square from each corner:
\n" ); document.write( "Width = x - 6
\n" ); document.write( "Length = 2x - 6
\n" ); document.write( "Volume of rectangular box
\n" ); document.write( "= length * width * height
\n" ); document.write( "= (2x - 6)*(x - 6)*(3) = 648
\n" ); document.write( "= 6x^2 - 54x + 108 = 648
\n" ); document.write( "= 6x^2 - 54x - 540 = 0
\n" ); document.write( "Divide thro'out by 6
\n" ); document.write( "= x^2 - 9x - 90 = 0
\n" ); document.write( "= (x + 6)(x - 15)= o
\n" ); document.write( "x = -6 (no answer as x < 0)
\n" ); document.write( "x = 15 inches.
\n" ); document.write( "Width = 9 inches
\n" ); document.write( "Length = 24 inches.
\n" ); document.write( "Height = 3 inches.
\n" ); document.write( "Hope this helps.
\n" ); document.write( ":-)\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "
\n" );