document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=976865>Question 976865</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find a8 when a1 = -6, d=2. use the formula for the general term ( the n^th term ) of an arithmetic sequence to find the indicated term of the sequence with the given first term , a1 and common difference , d.\r<BR>\n" );
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document.write( "a. 10<BR>\n" );
document.write( "b. 8<BR>\n" );
document.write( "c. -20<BR>\n" );
document.write( "d. -22\r<BR>\n" );
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document.write( "find the sum of the first 20 terms of the arithmetic sequence 5, 13, 21, 29\r<BR>\n" );
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document.write( "a. 1700<BR>\n" );
document.write( "b. 1620<BR>\n" );
document.write( "c. 1627<BR>\n" );
document.write( "d. 165 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #598440 by </B><A HREF=/tutors/aboutme.mpl?userid=Cromlix><B>Cromlix(4381)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Cromlix><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=Cromlix><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=598440\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Formula = a(n)= a(1) + (n - 1) d<BR>\n" );
document.write( "a(1) = -6  d = 2 <BR>\n" );
document.write( "a(8) = -6 + (8 - 1)2<BR>\n" );
document.write( "a(8) = -6 + 14<BR>\n" );
document.write( "a (8) = 8\r<BR>\n" );
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document.write( "Find the Sum<BR>\n" );
document.write( "a(1) = 5: n = 20: d = 8\r<BR>\n" );
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document.write( "a(n) = a(1) + (n - 1)d<BR>\n" );
document.write( "a(20) = 5 + (20 -1)8 <BR>\n" );
document.write( "a(20) = 5 + 152<BR>\n" );
document.write( "a(20) = 157\r<BR>\n" );
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document.write( "Sum formula = S(n) = n( a(1) + a(n))/2<BR>\n" );
document.write( "Now, let's find the sum:<BR>\n" );
document.write( "s(20) = [20( 5 + 157)]/2<BR>\n" );
document.write( "s(20) = 3240/2 = 1620<BR>\n" );
document.write( "Both answers are 'b'<BR>\n" );
document.write( "Hope this helps:-)\r<BR>\n" );
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document.write( " </SPAN>\n" );
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