document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=126327>Question 126327</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/1592009425/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> hello, can you help me to solve this question?<BR>\n" );
document.write( "x^2+9>0<BR>\n" );
document.write( "thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #92636 by </B><A HREF=/tutors/aboutme.mpl?userid=bucky><B>bucky(2189)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=bucky><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=92636\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A little \"tricky\". The answer to this question is that any real value of x (positive or<BR>\n" );
document.write( "negative) will satisfy this equation. Why? Because x^2 will always be a positive number. And <BR>\n" );
document.write( "when you add 9 to it, the result is still a positive number. And a positive number is greater<BR>\n" );
document.write( "than zero.<BR>\n" );
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document.write( "Let's just try a few values of x to demonstrate this. <BR>\n" );
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document.write( "Suppose x is +10. Then x^2 + 9 = 10^2 + 9 = 100 + 9 = +109. This certainly is greater than<BR>\n" );
document.write( "zero as is to be the case required by the problem.<BR>\n" );
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document.write( "Suppose x is +1. Then x^2 + 9 = 1^2 + 9 = 1 + 9 = +10.  This is still greater than zero.<BR>\n" );
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document.write( "Suppose x equals zero. Then x^2 + 9 = 0^2 + 9 = 0 + 9 = +9. Still greater than zero.<BR>\n" );
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document.write( "Now suppose x = -1. Then x^2 + 9 = (-1)^2 + 9 = 1 + 9 = +10. Still greater than zero.<BR>\n" );
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document.write( "Then suppose x = -10. Then x^2 + 9 = (-10)^2 + 9 = 100 + 9 = +109. And it is also greater<BR>\n" );
document.write( "than zero.<BR>\n" );
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document.write( "In fact if we graph y = x^2 + 9 the graph looks like:<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28500%2C500%2C+-15%2C15%2C-5%2C120%2Cx%5E2+%2B+9%29 ALIGN=MIDDLE  ALT=\"graph%28500%2C500%2C+-15%2C15%2C-5%2C120%2Cx%5E2+%2B+9%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "You can see from this graph that x^2 + 9 never has a value less than 9 no matter what the<BR>\n" );
document.write( "value along the x axis is. Therefore, x^2 + 9 is always greater than zero.<BR>\n" );
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document.write( "Hope this helps you to understand the problem a little better.<BR>\n" );
document.write( ". </SPAN>\n" );
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