document.write( "Question 259886: 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 #191359 by checkley77(12844) $\"\"$ $\"About$

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(11-2x)(14-2x)=80
\n" ); document.write( "154-28x-22x+4x^2=80
\n" ); document.write( "4x^2-50x+154-80=0
\n" ); document.write( "4x^2-50x+74=0
\n" ); document.write( "2(2x^2-25x+37)=0
\n" ); document.write( " $\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"$
\n" ); document.write( "x=(25+-sqrt[-25^2-4*2*37])/2*2
\n" ); document.write( "x=(25+-sqrt[625-296])/4
\n" ); document.write( "x=(25+-sqrt329)/4
\n" ); document.write( "x=(25+-18.138)/4
\n" ); document.write( "x=(25-18.138)/4
\n" ); document.write( "x=6.86/4
\n" ); document.write( "x=1.7154 ans. for the size of the squares cut from each corner.
\n" ); document.write( "Proof:
\n" ); document.write( "(11-2*1.7154)(14-2*1.7154)=80
\n" ); document.write( "(11-3.43)(14-3.43)=80
\n" ); document.write( "7.57*10.57=80
\n" ); document.write( "80~80 \n" ); document.write( "

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