document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=132593>Question 132593</A>: <I><SPAN STYLE=\"word-break: break-all;\"> THIS IS NOT A PROBLEM FROM A BOOK<BR>\n" );
document.write( "Problem: A business invests $10,000 in a savings account for two years.  At the beginning of the second year, an additional $3500 is invested.  At the end of the second year, the account balance is $15,569.75.  What was the annual interest rate?\r<BR>\n" );
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document.write( "I think that the interest rate is .0880745 through trial and error but I am unsure of how to solve this algebraically (or at least setting it up). The $10,000 has two years interest and the additional $3,500 accrues only one year interest. \r<BR>\n" );
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document.write( "Thanking in advance for any help on this. It is due today and I stayed up late last night trying to figure it out.  Thanks again! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #97101 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=97101\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let x=interest rate\r<BR>\n" );
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document.write( "15569.75=10000(1+x)^2+3500(1+x) __ 15569.75=10000(1+2x+x^2)+3500+3500x\r<BR>\n" );
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document.write( "dividing by 10000 __ 1.556975=1+2x+x^2+.35+.35x\r<BR>\n" );
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document.write( "subtracting 1.556975 __ 0=x^2+2.35x-.206975\r<BR>\n" );
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document.write( "using quadratic formula __ x=(-2.35ħsqrt(2.35^2-4(-.206975)))/2\r<BR>\n" );
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document.write( "x=.085 or 8.5% </SPAN>\n" );
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