document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=77707>Question 77707</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the area of the region between two concentric circles with radii 9 and 6.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #55722 by </B><A HREF=/tutors/aboutme.mpl?userid=funmath><B>funmath(2933)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=funmath><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=55722\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the area of the region between two concentric circles with radii 9 and 6. <BR>\n" );
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document.write( "If \"concentric\" means that the smaller circle is inside the larger circle, then we subtract the area of the smaller circle from the area of the larger circle.<BR>\n" );
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document.write( "The formula for the area of a circle is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28A=pi%2Ar%5E2%29 ALIGN=MIDDLE  ALT=\"highlight%28A=pi%2Ar%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > A=area, r=radius, pi is approximately 3.141592654<BR>\n" );
document.write( "The area of the larger circle with r=9 is: <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=pi%2A%289%29%5E2 ALIGN=MIDDLE  ALT=\"A=pi%2A%289%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=81%2Api ALIGN=MIDDLE  ALT=\"A=81%2Api\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The area of the smaller circle with r=6 is:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=pi%2A%286%29%5E2 ALIGN=MIDDLE  ALT=\"A=pi%2A%286%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=36%2Api ALIGN=MIDDLE  ALT=\"A=36%2Api\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The difference is:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=81%2Api-36%2Api=45%2Api ALIGN=MIDDLE  ALT=\"81%2Api-36%2Api=45%2Api\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "You can approximate this to whatever your teacher wants.  A lot will let you use pi=3.14<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=45%2A3.14=141.3 ALIGN=MIDDLE  ALT=\"45%2A3.14=141.3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Happy Calculating!!! </SPAN>\n" );
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