document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=854209>Question 854209</A>: <I><SPAN STYLE=\"word-break: break-all;\"> There are four numbers in an Arithmetic Progression. The sum of the two extremes is 8, and the product of the middle two numbers is 15. What are the numbers?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #514499 by </B><A HREF=/tutors/aboutme.mpl?userid=richwmiller><B>richwmiller(17219)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richwmiller><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=richwmiller><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=514499\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> an = a + (n - 1)d<BR>\n" );
document.write( "a1+a4 = 2a+ 3d=8<BR>\n" );
document.write( "a2*a3=15<BR>\n" );
document.write( "  (a + 1d)( a + 2d)=15<BR>\n" );
document.write( "a^2+ad+2ad+2d^2=15<BR>\n" );
document.write( "a^2+3ad+2d^2=15,<BR>\n" );
document.write( "2a+ 3d=8<BR>\n" );
document.write( "Two possible progressions\r<BR>\n" );
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document.write( "a = 1,   d = 2<BR>\n" );
document.write( "1,3,5,7\r<BR>\n" );
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document.write( "or <BR>\n" );
document.write( "a = 7,   d = -2<BR>\n" );
document.write( "7,5,3,1\r<BR>\n" );
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