document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=258859>Question 258859</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the area of a circular ring is 90. if the radius of the outer circle forming the ring is 7, what is the radius of the inner circle of the ring? (assume the circles forming the ring have the same center.) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #190585 by </B><A HREF=/tutors/aboutme.mpl?userid=Stitch><B>Stitch(470)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Stitch><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=190585\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The Area of a circle is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3.14%28Pi%29+%2A+R%5E2 ALIGN=MIDDLE  ALT=\"3.14%28Pi%29+%2A+R%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The Area of the circular ring is the difference of the area of the larger circle minus the area of the inner circle.\r<BR>\n" );
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document.write( "Given: Radius of the outer circle is 7.  The difference of the areas between the two circles is 90\r<BR>\n" );
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document.write( "Our Equation:  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3.14%2A7%5E2+-+3.14%2AA%5E2+=+90 ALIGN=MIDDLE  ALT=\"3.14%2A7%5E2+-+3.14%2AA%5E2+=+90\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The left side of the equation can be simplified by dividing both terms by 3.14<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3.14+%2A+%287%5E2+-+A%5E2%29+=+90 ALIGN=MIDDLE  ALT=\"3.14+%2A+%287%5E2+-+A%5E2%29+=+90\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Divide both sides by 3.14<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7%5E2+-+A%5E2+=+28.65 ALIGN=MIDDLE  ALT=\"7%5E2+-+A%5E2+=+28.65\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Simplify the equation<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=49+-+A%5E2+=+28.65 ALIGN=MIDDLE  ALT=\"49+-+A%5E2+=+28.65\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Add A^2 to both sides<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=49+=+28.65+%2B+A%5E2 ALIGN=MIDDLE  ALT=\"49+=+28.65+%2B+A%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Subtract 28.65 from both sides<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20.35+=+A%5E2 ALIGN=MIDDLE  ALT=\"20.35+=+A%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Take the square root of both sides<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%284.5+=+A%29 ALIGN=MIDDLE  ALT=\"highlight%284.5+=+A%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The radius of the inner ring is 4.5<BR>\n" );
document.write( " </SPAN>\n" );
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