document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=739949>Question 739949</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This problem includes \"Pie\"=3.14. I can't find a way to symbolize \"pie\". I hope this doesn't affect your ability to help. Also this is part of factoring polynomials.\r<BR>\n" );
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document.write( "\"The sum of the areas of two circles is 169pie square inches. the length of a radius of the smaller circle is 7 inches less than the length of a radius of the larger circle. Find the length of the larger circle.\"\r<BR>\n" );
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document.write( "I am not sure how to set this problem up to solve it. I don't remember how to find the area of a circle.\r<BR>\n" );
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document.write( "Any step by step help would be appreciated. thank you! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #451421 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=451421\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \"The sum of the areas of two circles is 169pie square inches. the length of a radius of the smaller circle is 7 inches less than the length of a radius of the larger circle. Find the length of a radius of the larger circle.\"<BR>\n" );
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document.write( "area of a circle=&#960;r^2<BR>\n" );
document.write( "let r=radius of larger circle<BR>\n" );
document.write( "area of larger circle=&#960;r^2<BR>\n" );
document.write( "r-7=radius of smaller circle<BR>\n" );
document.write( "area of smaller circle=&#960;(r-7)^2<BR>\n" );
document.write( "sum of the areas of two circles is 169pie square inches<BR>\n" );
document.write( "&#960;r^2+&#960;(r-7)^2=169&#960;<BR>\n" );
document.write( "factor out &#960;<BR>\n" );
document.write( "r^2+(r-7)^2=169<BR>\n" );
document.write( "r^2+r^2-14r+49=169<BR>\n" );
document.write( "2r^2-14r-120=0<BR>\n" );
document.write( "r^2-7r-60=0<BR>\n" );
document.write( "(r+5)(r-12)=0<BR>\n" );
document.write( "r=-5 (reject, r>0)<BR>\n" );
document.write( "or<BR>\n" );
document.write( "r=12<BR>\n" );
document.write( "r-7=5<BR>\n" );
document.write( "radius of larger circle=12 sq in<BR>\n" );
document.write( "radius of smaller circle=5 sq in </SPAN>\n" );
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