document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1069541>Question 1069541</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1. log x - log (x+2)=1\r<BR>\n" );
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document.write( "2. (4^x)-40=3*2^x\r<BR>\n" );
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document.write( "3.Det. Robert Goren is investigating a homicide, and the medical examiner tells him that when he arrived at 6:00 p.m., the body had a temperature of 95.3 degrees Fahrenheit. By the time Nichols had arrived an hour later (at 7:00), he checks again and determines the temperature to be 94.9 degrees. The ambient air temperature is 90 degrees. Use the equation &#119879;(&#119905;) = &#119886;&#119890;^(&#8722;&#119896;&#119905;) + 90 to determine when the victim was killed. (The normal body temperature is 98.6 degrees. Round k to 3 decimal places and find the time of death to the nearest minute.\r<BR>\n" );
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document.write( "For number 1, I got -20/9, but it can't be negative so I'm confused. Thank you for answering!<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 #684750 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=684750\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1. log x - log (x+2)=1<BR>\n" );
document.write( "Assuming base 10:<BR>\n" );
document.write( "log(x) - log(x+2)=1 = log(10)<BR>\n" );
document.write( "log(x/(x+2)) = log(10)<BR>\n" );
document.write( "x/(x+2) = 10<BR>\n" );
document.write( "x = 10x + 20<BR>\n" );
document.write( "x = -20/9<BR>\n" );
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document.write( "But, log(-20/9) is not allowed.<BR>\n" );
document.write( "--> no solution.<BR>\n" );
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document.write( "2. (4^x)-40=3*2^x<BR>\n" );
document.write( "2^(2x)-40 = 3*2^x<BR>\n" );
document.write( "2^(2x) - 3*2^x - 40 = 0<BR>\n" );
document.write( "(2^x - 8)*(2^x + 5) = 0<BR>\n" );
document.write( "2^x = 8<BR>\n" );
document.write( "x = 3<BR>\n" );
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document.write( "2^x = -5 ignore<BR>\n" );
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document.write( "3.Det. Robert Goren is investigating a homicide, and the medical examiner tells him that when he arrived at 6:00 p.m., the body had a temperature of 95.3 degrees Fahrenheit.  An hour later (at 7:00), he checks again and determines the temperature to be 94.9 degrees. The ambient air temperature is 90 degrees. Use the equation D(t) = a*e^(-kt) + 90 to determine when the victim was killed. (The normal body temperature is 98.6 degrees. Round k to 3 decimal places and find the time of death to the nearest minute.<BR>\n" );
document.write( "I'll use D for degrees.<BR>\n" );
document.write( "D(t) = a*e^(-kt) + 90<BR>\n" );
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document.write( "D(0) = a*e^(-kt) + 90 = 95.3  (At 6PM)<BR>\n" );
document.write( "a*e^(-kt) + 90 = 95.3<BR>\n" );
document.write( "Have to finish later.<BR>\n" );
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document.write( "For number 1, I got -20/9, but it can't be negative so I'm confused.<BR>\n" );
document.write( "The solution is negative --> the equation is not valid.<BR>\n" );
document.write( "--> no solution.<BR>\n" );
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