document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=378345>Question 378345</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Write a rule for the nth term of the arithmetic sequence that has the 2 given terms. \r<BR>\n" );
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document.write( "A(20)=240, A(15)=170\r<BR>\n" );
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document.write( "I understand how to write a rule for a sequence using the A(n)=A(1)+(n-1)d, but I do not understand how to get a rule without having the first term and common difference. Any help is really appreciated!\r<BR>\n" );
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document.write( "Thanks so much! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #268836 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=268836\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> you have the formula\r<BR>\n" );
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document.write( "how many differences between A(15) and A(20)?<BR>\n" );
document.write( "what's the numerical difference between the terms?\r<BR>\n" );
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document.write( "5d = 240 - 170\r<BR>\n" );
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document.write( "plug the value of d into your formula to find A(1) </SPAN>\n" );
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