document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=357859>Question 357859</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi everyone i hope someone can help me . im using the \r<BR>\n" );
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document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+Sn=+%28n%2F2%29+%282a+%2B%28n-1%29d%29+ ALIGN=MIDDLE  ALT=\"+Sn=+%28n%2F2%29+%282a+%2B%28n-1%29d%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  formula with a=first term and d= common difference\r<BR>\n" );
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document.write( "im trying to solve for a if S21=315 and d=3 .im a little confused what to do when i get \r<BR>\n" );
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document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315+=+%2821%2F2+%29%282a+%2B+%2821-1%293%29 ALIGN=MIDDLE  ALT=\"315+=+%2821%2F2+%29%282a+%2B+%2821-1%293%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > so i need to solve for a<BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315+=+%2821%2F2%29+%282a+%2B+60%29 ALIGN=MIDDLE  ALT=\"315+=+%2821%2F2%29+%282a+%2B+60%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > ?? this is where i get my problem. how do i get a on its own??\r<BR>\n" );
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document.write( "Iv tried <BR>\n" );
document.write( "          <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315+=+%2821%2F2%29+%2862a%29 ALIGN=MIDDLE  ALT=\"315+=+%2821%2F2%29+%2862a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "          <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315+=+1302a%2F2 ALIGN=MIDDLE  ALT=\"315+=+1302a%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "          <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315+=+651a ALIGN=MIDDLE  ALT=\"315+=+651a\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "im not sure from here?? do i just subtract 651 from both sides to find a. im not sure that answer dose not look right.?? any help would be appreciated :) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #255442 by </B><A HREF=/tutors/aboutme.mpl?userid=mobosecomin><B>mobosecomin(1)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mobosecomin><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=255442\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> ok so i solved this myself it was just a silly order of precedence problem i was having \r<BR>\n" );
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document.write( "when i got<BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315+=+%2821%2F2%29+%282a+%2B+60%29 ALIGN=MIDDLE  ALT=\"315+=+%2821%2F2%29+%282a+%2B+60%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >  i should have <BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315+=+10.5+++%282a+%2B+60%29 ALIGN=MIDDLE  ALT=\"315+=+10.5+++%282a+%2B+60%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >  multiply everything in the brackets by 10.5<BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315+=+21a+%2B+630 ALIGN=MIDDLE  ALT=\"315+=+21a+%2B+630\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315-630+=+21a++ ALIGN=MIDDLE  ALT=\"315-630+=+21a++\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-315+=+++21a+++ ALIGN=MIDDLE  ALT=\"-315+=+++21a+++\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+-15+=+a+++++++ ALIGN=MIDDLE  ALT=\"+-15+=+a+++++++\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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