document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=70015>Question 70015</A>: <I><SPAN STYLE=\"word-break: break-all;\"> what is the y-intercept for x^2-2x-8 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #49865 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=49865\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Set y equal to the function you were given.  This results in the equation:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=x%5E2-2x-8 ALIGN=MIDDLE  ALT=\"y=x%5E2-2x-8\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Now think about the general structure of a graph.  If you have a point on the Y-axis,<BR>\n" );
document.write( "what is the value of X for that point.  Every point on the Y-axis has a corresponding<BR>\n" );
document.write( "X value of zero!!!  Think of +3 on the Y-axis.  This would be the point (0,+3).  Similarly<BR>\n" );
document.write( "the point -5 on the Y-axis would be (0, -5) and so on.\r<BR>\n" );
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document.write( "So for the above equation we can simply set x equal to zero to find the corresponding<BR>\n" );
document.write( "value of y that satisfies the equation.  Start with:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=x%5E2-2x-8 ALIGN=MIDDLE  ALT=\"y=x%5E2-2x-8\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Plug in zero for x.  This causes the terms that contain an x to be zero.  What you are<BR>\n" );
document.write( "left with is:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=0+%2B+0+-+8 ALIGN=MIDDLE  ALT=\"y=0+%2B+0+-+8\"   DISABLED_style= \"max-width:90%; height:auto;\" > which simplifies to just <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+-8 ALIGN=MIDDLE  ALT=\"y+=+-8\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The Y-intercept occurs at y = -8 or at the point (0,-8).  It's harder to explain than it<BR>\n" );
document.write( "is to just set x equal to zero and determine what is left on the right side of the equation.\r<BR>\n" );
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document.write( "Hope this helps you understand how to find Y intercepts.   </SPAN>\n" );
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