document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=153694>Question 153694</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve the following problem:\r<BR>\n" );
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document.write( "State the x-intercepts of the graph of the equation. Then find the coordinates of the vertex.\r<BR>\n" );
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document.write( "y=(x+3)(x-5) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #113139 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=113139\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> when the graph crosses the x-axis (x-intercept), the value of y is zero<BR>\n" );
document.write( "__ this happens when x+3=0 or x-5=0\r<BR>\n" );
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document.write( "so the x-intercepts are -3 and 5\r<BR>\n" );
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document.write( "the x-coordinate of the vertex is midway between the intercepts (on the axis of symmetry)<BR>\n" );
document.write( "__ midway between -3 and 5 is 1 ([5-3]/2)\r<BR>\n" );
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document.write( "substituting 1 for x in the equation gives y=(1+3)(1-5) or y=-16\r<BR>\n" );
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document.write( "so the vertex is at (1,-16) </SPAN>\n" );
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