document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=192689>Question 192689</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find three numbers in arithmetic progression whose sum is 21 and whose product is 180 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #144627 by </B><A HREF=/tutors/aboutme.mpl?userid=RAY100><B>RAY100(1637)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=RAY100><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=144627\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let  arithmetic  sequence  be  x,  x+d, x+2d.   sum  is  3x +3d=21,  or  x+d=7  (KEY)\r<BR>\n" );
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document.write( "multiply (x) (x+d) (x+2d) = 180<BR>\n" );
document.write( "x^3+3dx^2+2d^2x=180  (KEY)\r<BR>\n" );
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document.write( "but  x+d=7,  therefore  x=7-d   (KEY)\r<BR>\n" );
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document.write( "substitution  and  simplyfing\r<BR>\n" );
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document.write( "-7d^2+163=0\r<BR>\n" );
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document.write( "d=4.8255   ANSWER\r<BR>\n" );
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document.write( "but  x=7-d,  x=7-4.8255 , x=2.1744  ANSWER\r<BR>\n" );
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document.write( "set  is  2.1744,  7,  11.8254   SUMMARY  ANSWER\r<BR>\n" );
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document.write( "check<BR>\n" );
document.write( "2.1744 +(2.1744+4.8255)+(2.1744+4.8255+4.8255)=21  ok\r<BR>\n" );
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document.write( "2.1744 *  (2.1744+4.8255)*(2.1744+4.8255+4.8255) = 180  ok<BR>\n" );
document.write( "  </SPAN>\n" );
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