document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1009912>Question 1009912</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Write an exponential function such that f(-2) = 25 and f(1) = 8/5. <BR>\n" );
document.write( "I got F(x) = 6.25*(0.4) &#879;  but my teacher tells me its not 6.25 but 4. Where do I get the 4 from? \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 #625378 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=625378\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28x%29=ab%5Ex ALIGN=MIDDLE  ALT=\"f%28x%29=ab%5Ex\"   DISABLED_style= \"max-width:90%; height:auto;\" > can be the form of the exponential function.<BR>\n" );
document.write( "Two points are   (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2 ALIGN=MIDDLE  ALT=\"-2\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=25 ALIGN=MIDDLE  ALT=\"25\"   DISABLED_style= \"max-width:90%; height:auto;\" >) and (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1 ALIGN=MIDDLE  ALT=\"1\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8%2F5 ALIGN=MIDDLE  ALT=\"8%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >).\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=25=ab%5E%28-2%29 ALIGN=MIDDLE  ALT=\"25=ab%5E%28-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1=ab%5E%288%2F5%29 ALIGN=MIDDLE  ALT=\"1=ab%5E%288%2F5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "solve the system:\r<BR>\n" );
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document.write( "Take logarithms of both sides, base of your choice, and you will have a linear equation.  You would need to make an adjustment to the vertical axis component of your given points.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%2825%29=log%28ab%5E%28-2%29%29 ALIGN=MIDDLE  ALT=\"log%2825%29=log%28ab%5E%28-2%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%285%5E2%29=log%28a%29%2Blog%28b%5E%28-2%29%29 ALIGN=MIDDLE  ALT=\"log%285%5E2%29=log%28a%29%2Blog%28b%5E%28-2%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2log%285%29=log%28a%29%2B%28-2%29log%28b%29 ALIGN=MIDDLE  ALT=\"2log%285%29=log%28a%29%2B%28-2%29log%28b%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2log%285%29=log%28a%29-2log%28b%29 ALIGN=MIDDLE  ALT=\"2log%285%29=log%28a%29-2log%28b%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.......eq.1\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%281%29=log%28ab%5E%288%2F5%29%29 ALIGN=MIDDLE  ALT=\"log%281%29=log%28ab%5E%288%2F5%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0=log%28a%29%2Blog%28b%5E%288%2F5%29%29 ALIGN=MIDDLE  ALT=\"0=log%28a%29%2Blog%28b%5E%288%2F5%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0=log%28a%29%2B%288%2F5%29log%28b%29 ALIGN=MIDDLE  ALT=\"0=log%28a%29%2B%288%2F5%29log%28b%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.......eq.2\r<BR>\n" );
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document.write( "subtract eq.1 from eq.2\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0-2log%285%29=log%28a%29-log%28a%29%2B%288%2F5%29log%28b%29%2B2log%28b%29 ALIGN=MIDDLE  ALT=\"0-2log%285%29=log%28a%29-log%28a%29%2B%288%2F5%29log%28b%29%2B2log%28b%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2log%285%29=%288%2F5%29log%28b%29%2B%2810%2F5%29log%28b%29 ALIGN=MIDDLE  ALT=\"-2log%285%29=%288%2F5%29log%28b%29%2B%2810%2F5%29log%28b%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2log%285%29=%2818%2F5%29log%28b%29 ALIGN=MIDDLE  ALT=\"-2log%285%29=%2818%2F5%29log%28b%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%285%5E-2%29=log%28b%5E%2818%2F5%29%29 ALIGN=MIDDLE  ALT=\"log%285%5E-2%29=log%28b%5E%2818%2F5%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%5E-2=b%5E%2818%2F5%29 ALIGN=MIDDLE  ALT=\"5%5E-2=b%5E%2818%2F5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b+=+1%2F5%5E%285%2F9%29 ALIGN=MIDDLE  ALT=\"b+=+1%2F5%5E%285%2F9%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b+=+0.4 ALIGN=MIDDLE  ALT=\"b+=+0.4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "now find <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a ALIGN=MIDDLE  ALT=\"a\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%28a%29=-%288%2F5%29log%28b%29 ALIGN=MIDDLE  ALT=\"log%28a%29=-%288%2F5%29log%28b%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > from eq.2\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%28a%29=-%288%2F5%29log%280.4%29 ALIGN=MIDDLE  ALT=\"log%28a%29=-%288%2F5%29log%280.4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%28a%29=log%280.4%5E%28-%288%2F5%29%29%29 ALIGN=MIDDLE  ALT=\"log%28a%29=log%280.4%5E%28-%288%2F5%29%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=0.4%5E%28-%288%2F5%29%29 ALIGN=MIDDLE  ALT=\"a=0.4%5E%28-%288%2F5%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=1%2F%280.4%5E%288%2F5%29%29 ALIGN=MIDDLE  ALT=\"a=1%2F%280.4%5E%288%2F5%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=1%2F0.230832 ALIGN=MIDDLE  ALT=\"a=1%2F0.230832\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=4.3321549871 ALIGN=MIDDLE  ALT=\"a=4.3321549871\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=4 ALIGN=MIDDLE  ALT=\"a=4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "so, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28x%29=4%280.4%29%5Ex ALIGN=MIDDLE  ALT=\"f%28x%29=4%280.4%29%5Ex\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );