document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1138605>Question 1138605</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A rectangular sheet of tin is 15cm long and 9cm wide. A uniform strip is to be cut off around the sheet. The examining area is 112cm squared. Calculate the width of the strip. The answer is 0.5 cm.\r<BR>\n" );
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document.write( "What I have got so far: At - As =  112 <BR>\n" );
document.write( "At = 135\r<BR>\n" );
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document.write( "135 - As = 112<BR>\n" );
document.write( "23 = As\r<BR>\n" );
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document.write( "23 = (15-2x) (9-2x)<BR>\n" );
document.write( "4x^2 - 12x + 28<BR>\n" );
document.write( "4(x^2 -12x +28)<BR>\n" );
document.write( "x=14 </SPAN>\n" );
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document.write( "The \"examining\" area?  Really now -- you should look at what you have written before you post your question.<br><BR>\n" );
document.write( "From the context of the problem, it is clear that you mean the REMAINING area is 112cm^2....<br><BR>\n" );
document.write( "You don't need algebra to solve this problem.<br><BR>\n" );
document.write( "The difference between the length and width is 6cm; if the strip cut off is uniform, then the length and width of the remaining rectangular piece of tin will still differ by 6cm.<br><BR>\n" );
document.write( "So look for a way to factor 112 as the product of two integers whose difference is 6.<br><BR>\n" );
document.write( "Even without having any insight into the answer, a little trial and error should find the new dimensions to be 14cm by 8cm.<br><BR>\n" );
document.write( "So the width and length have both been shorted by 1cm; since the uniform strip was cut off on all four sides, the width of the strip is 0.5cm. </SPAN>\n" );
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