document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=257304>Question 257304</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a circular pool measure 14 feet across. one cubic yard of concrete is to be used to create a circular border of uniform width around the pool. if the border is to have a depth of 3 inches, how would will the border be </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #189239 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=189239\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a circular pool measure 14 feet across. one cubic yard of concrete is to be used to create a circular border of uniform width around the pool.<BR>\n" );
document.write( " if the border is to have a depth of 3 inches, how would will the border be<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Change 1 cu yd to cu ft<BR>\n" );
document.write( "3*3*3 = 27 cu/ft of concrete<BR>\n" );
document.write( "Find the area covered if 3\" thick: 3\" = 3/12 = .25 ft<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=27%2F.25 ALIGN=MIDDLE  ALT=\"27%2F.25\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 108 sq/ft<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Let x = width of the concrete border<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Pool radius = 7 ft (measures 14' across)<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Overall area - pool area = 108 sq/ft<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi%2A%28x%2B7%29%5E2 ALIGN=MIDDLE  ALT=\"pi%2A%28x%2B7%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi%2A7%5E2 ALIGN=MIDDLE  ALT=\"pi%2A7%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 108<BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi%28x%5E2+%2B+14x+%2B+49%29 ALIGN=MIDDLE  ALT=\"pi%28x%5E2+%2B+14x+%2B+49%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > - (153.938) = 108<BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi%28x%5E2+%2B+14x+%2B+49%29 ALIGN=MIDDLE  ALT=\"pi%28x%5E2+%2B+14x+%2B+49%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 108 + 153.938<BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi%28x%5E2+%2B+14x+%2B+49%29 ALIGN=MIDDLE  ALT=\"pi%28x%5E2+%2B+14x+%2B+49%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 261.938<BR>\n" );
document.write( "Divide both sides by Pi<BR>\n" );
document.write( "x^2 + 14x + 49 = 83.377<BR>\n" );
document.write( ":<BR>\n" );
document.write( "x^2 + 14x + 49 - 83.377 = 0<BR>\n" );
document.write( ":<BR>\n" );
document.write( "x^2 + 14x - 34.377 = 0<BR>\n" );
document.write( "Solve this using the quadratic formula<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "In this problem a=1; b=14; c=-34.377<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-14+%2B-+sqrt%2814%5E2-4%2A1%2A-34.377+%29%29%2F%282%2A1%29+ ALIGN=MIDDLE  ALT=\"x+=+%28-14+%2B-+sqrt%2814%5E2-4%2A1%2A-34.377+%29%29%2F%282%2A1%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-14+%2B-+sqrt%28196-%28-137.508%29+%29%29%2F2+ ALIGN=MIDDLE  ALT=\"x+=+%28-14+%2B-+sqrt%28196-%28-137.508%29+%29%29%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-14+%2B-+sqrt%28333.508+%29%29%2F2+ ALIGN=MIDDLE  ALT=\"x+=+%28-14+%2B-+sqrt%28333.508+%29%29%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Positive solution is what we want here<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-14+%2B+18.262%29%2F2+ ALIGN=MIDDLE  ALT=\"x+=+%28-14+%2B+18.262%29%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4.262%2F2 ALIGN=MIDDLE  ALT=\"4.262%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = 2.13 ft, the width of the concrete border (2' 1.6\")<BR>\n" );
document.write( ":<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Check this solution on a calc, enter<BR>\n" );
document.write( "(pi*9.13^2) - (pi*7^2) = 107.9 ~ 108 sq/ft<BR>\n" );
document.write( ":<BR>\n" );
document.write( "108 * .25 = 27 cu.ft which is 1 cu yd\r<BR>\n" );
document.write( "\n" );
document.write( " <BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );