document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=237423>Question 237423</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An open box is made from a thin square metal sheet measuring 10cm by 10cm. Four squares of side x centimeters are cut away and the remaining sides are folded upwards to make a boz of depth x centimeters\r<BR>\n" );
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document.write( "a-Show that the external surface area Acm^2 is given by the formula A=100-4x^2 where 0<x<5<BR>\n" );
document.write( "b-Draw the graph of A against x by first constructing a table of values. <BR>\n" );
document.write( "c- Use your graph to find values of x which will produce a box with an external area of between 50cm^3 and 75cm^3, inclusive.\r<BR>\n" );
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document.write( "Please please help me solve this question. It is really urgent!!<BR>\n" );
document.write( "Thanks !!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #174609 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=174609\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Garamond\" size=\"+2\">\r<BR>\n" );
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document.write( "You need to show that the external surface area is given by the function\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ A(x)\ =\ 100\ -\ 4x^2\">\r<BR>\n" );
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document.write( "Where\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ 0\ <\ x\ <\ 5\">\r<BR>\n" );
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document.write( "The external surface area of the box is just the area of one side of the metal after you have cut the corners out but before you bend up the sides.  Since the metal piece began life as 10cm by 10cm, the area before you cut out the corners was 100.  Each corner cut out is an <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large x\"> by <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large x\"> square, so each corner has an area of <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large x^2\">.  And there are 4 of these squares cut out.  So from the area of the original sheet of metal, 100, we have to subtract 4 times the area of one of the cutout squares, hence:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ A(x)\ =\ 100\ -\ 4x^2\">\r<BR>\n" );
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document.write( "Part b.  Just pick some values from the range <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE 0\ <\ x\ <\ 5\"> and substitute each of them into the function.  Each of the selected values and the resulting function value forms a row in your table.  Each row in the table makes an ordered pair that can be plotted.  Plot a few points and then draw a smooth curve.\r<BR>\n" );
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document.write( "Part c is just reading the graph.\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi} + 1 = 0\"><BR>\n" );
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