document.write( "Question 259875: Open-top box. Thomas is going to make an open-top box
\n" ); document.write( "by cutting equal squares from the four corners of an
\n" ); document.write( "11 inch by 14 inch sheet of cardboard and folding up the
\n" ); document.write( "sides. If the area of the base is to be 80 square inches, then
\n" ); document.write( "what size square should be cut from each corner? \n" ); document.write( "
Algebra.Com's Answer #191379 by ankor@dixie-net.com(22740)\"\" \"About 
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make an open-top box by cutting equal squares from the four corners of an
\n" ); document.write( "11 inch by 14 inch sheet of cardboard and folding up the sides.
\n" ); document.write( " If the area of the base is to be 80 square inches,
\n" ); document.write( " then what size square should be cut from each corner?
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\n" ); document.write( "Let x = the side of the 4 squares to be cut from each corner
\n" ); document.write( "then the dimensions of the base will be:
\n" ); document.write( "(11-2x) by (14-2x)
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\n" ); document.write( "Given the area, we have:
\n" ); document.write( "(11-2x)*(14-2x) = 80
\n" ); document.write( "FOIL
\n" ); document.write( "154 - 22x - 28x + 4x^2 = 80
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\n" ); document.write( "4x^2 - 50x + 154 - 80 = 0
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\n" ); document.write( "A quadratic equation
\n" ); document.write( "4x^2 - 50x + 74 = 0
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\n" ); document.write( "simplify divide by 2
\n" ); document.write( "2x^2 - 25x + 37 = 0
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\n" ); document.write( "Solve this using the quadratic formula; a=2; b=-25, c=37
\n" ); document.write( "you should get the reasonable answer of
\n" ); document.write( "x = 1.715 inches is the side of the removed squares
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\n" ); document.write( "Check this on a calc: enter (11-2(1.715)) * (14-2(1.715)) = 80.015 ~ 80 \n" ); document.write( "
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