document.write( "Question 80882: Thomas is going to make an open-top box by cutting equal squares from the four corners of an 11inch by 14 inch sheet of cardboard and folding up the sides. If the area of the base is to be 80 square inches, then what size square should be cut from each corner? \n" ); document.write( "
Algebra.Com's Answer #58023 by ankor@dixie-net.com(22740)\"\" \"About 
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Thomas is going to make an open-top box by cutting equal squares from the four corners of an 11 inch by 14 inch sheet of cardboard and folding up the sides. If the area of the base is to be 80 square inches, then what size square should be cut from each corner?
\n" ); document.write( ":
\n" ); document.write( "Draw rough diagram of this, a rectangle 11 by 14, with squares cut out at each
\n" ); document.write( "corner. Label the side of these squares as x. It will be apparent to you that
\n" ); document.write( "the dimensions of the base will be (11-2x) by (14-2x). It's area is given as 80
\n" ); document.write( ":
\n" ); document.write( "A simple area equation:
\n" ); document.write( "(11-2x) * (14-2x) = 80
\n" ); document.write( "FOIL
\n" ); document.write( "154 - 50x + 4x^2 = 80
\n" ); document.write( ":
\n" ); document.write( "4x^2 - 50x + 154 - 80 = 0
\n" ); document.write( ":
\n" ); document.write( "4x^2 - 50x + 74 = 0
\n" ); document.write( ":
\n" ); document.write( "Not easily factored, so use the quadratic formula: a=4, b=-50, c=74
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "\"x+=+%28-%28-50%29+%2B-+sqrt%28-50%5E2-4%2A4%2A74+%29%29%2F%282%2A4%29+\"
\n" ); document.write( "\"x+=+%28%2B50+%2B-+sqrt%28+2500+-+1184%29%29%2F%288%29+\"
\n" ); document.write( "\"x+=+%28%2B50+%2B-+sqrt%281316%29%29%2F%288%29+\"
\n" ); document.write( "\"x+=+%28%2B50+%2B-+36.2767%29%2F%288%29+\"
\n" ); document.write( "Two solutions:
\n" ); document.write( "\"x+=+%28%2B50+%2B+36.2767%29%2F%288%29+\"
\n" ); document.write( "\"x+=+%28%2B86.2767%29%2F%288%29+\"
\n" ); document.write( "x = +10.78
\n" ); document.write( "and
\n" ); document.write( "\"x+=+%28%2B50+-+36.2767%29%2F%288%29+\"
\n" ); document.write( "\"x+=+%28%2B13.7232%29%2F%288%29+\"
\n" ); document.write( "x = +1.715
\n" ); document.write( ":
\n" ); document.write( "The smaller solution is the only one that makes sense:
\n" ); document.write( "A 1.715 inch square should be cut from each corner
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check our solution by finding the area of the base with these dimensions:
\n" ); document.write( "Find 2x: 2*1.715 = 3.43
\n" ); document.write( "(11 - 3.43) * (14 - 3.43) = 80.01 ~ 80 sq in
\n" ); document.write( ":
\n" ); document.write( "How about this? Did it seem logical and understandable to you?
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