document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=186786>Question 186786</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Could someone help me with this one;\r<BR>\n" );
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document.write( "sqrt(-25)sqrt(-9)<BR>\n" );
document.write( "My answer was 15, but it got marked wrong on my test, but sqrt(-25)=-5 and sqrt(-9)=-3 and -5*-3=15 so I dont really understand why its wrong.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #140004 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=140004\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Note: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28-25%29%3C%3E-5 ALIGN=MIDDLE  ALT=\"sqrt%28-25%29%3C%3E-5\"   DISABLED_style= \"max-width:90%; height:auto;\" > and  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28-9%29%3C%3E-3 ALIGN=MIDDLE  ALT=\"sqrt%28-9%29%3C%3E-3\"   DISABLED_style= \"max-width:90%; height:auto;\" > since you CANNOT take the square root of a negative number. Instead, we denote the value <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=i=sqrt%28-1%29 ALIGN=MIDDLE  ALT=\"i=sqrt%28-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > where 'i' is an imaginary number.\r<BR>\n" );
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document.write( "So...\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28-25%29%2Asqrt%28-9%29=sqrt%28-1%2A25%29%2Asqrt%28-1%2A9%29=sqrt%28-1%29%2Asqrt%2825%29%2Asqrt%28-1%29%2Asqrt%289%29=i%2A5%2Ai%2A3=%285%2A3%29%2A%28i%2Ai%29=15i%5E2=15%28-1%29=-15 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "This means that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28-25%29%2Asqrt%28-9%29=-15 ALIGN=MIDDLE  ALT=\"sqrt%28-25%29%2Asqrt%28-9%29=-15\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So you were off by a sign.  </SPAN>\n" );
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