document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=5429>Question 5429</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I was womdering if you could explain how to answer 3 problems:\r<BR>\n" );
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document.write( "1) x^2+x>0\r<BR>\n" );
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document.write( "2) x+3<-2/x\r<BR>\n" );
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document.write( "3) y=x^2+4x+1\r<BR>\n" );
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document.write( "Please explain each step so that I can use these are sample and model problems.\r<BR>\n" );
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document.write( "Thanks,\r<BR>\n" );
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document.write( "Char </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #2871 by </B><A HREF=/tutors/aboutme.mpl?userid=longjonsilver><B>longjonsilver(2297)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=longjonsilver><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=longjonsilver><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=2871\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1. factorise it first to x(x+1) = 0\r<BR>\n" );
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document.write( "then we can say that either x=0 or x+1=0, so answers are x=0 or x=-1.\r<BR>\n" );
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document.write( "2. x+3<-2/x --> get rid of the fraction by multiplying every term by x, to give <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+%2B+3x%3C-2 ALIGN=MIDDLE  ALT=\"x%5E2+%2B+3x%3C-2\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+%2B+3x+%2B+2+%3C+0 ALIGN=MIDDLE  ALT=\"x%5E2+%2B+3x+%2B+2+%3C+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >. First lets, find where <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+%2B+3x+%2B+2+=+0 ALIGN=MIDDLE  ALT=\"x%5E2+%2B+3x+%2B+2+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" > --> we again factorise, to give (x+1)(x+2) = 0. So x=-1 or x=-2.\r<BR>\n" );
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document.write( "So going back to the question, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+%2B+3x+%2B+2+%3C+0 ALIGN=MIDDLE  ALT=\"x%5E2+%2B+3x+%2B+2+%3C+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >, where is the curve less than zero: we have found where the curve crosses the x-axis (at x=-2 and x=-1) and the curve is a u=shape, so the curve has -ve y-values between the x=-2 and x=-1 values: plot it to see this.\r<BR>\n" );
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document.write( "So answer is -2<x<-1.\r<BR>\n" );
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document.write( "3. <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=x%5E2%2B4x%2B1 ALIGN=MIDDLE  ALT=\"y=x%5E2%2B4x%2B1\"   DISABLED_style= \"max-width:90%; height:auto;\" >. This does not factorise, so you will have to use the quadratic formula to work out the x-values. You have a go at this.\r<BR>\n" );
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document.write( "jon.<BR>\n" );
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