document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=201679>Question 201679</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the x- and y-intercepts. If no x-intercepts exist, state so.\r<BR>\n" );
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document.write( "f(x) = 15x^2 - 20x - 9<BR>\n" );
document.write( " A) ((20 (+or-) sqrt 940)/(2)) , (0, -9)<BR>\n" );
document.write( " B) ((20 (+or-) sqrt 940)/(2)) , (0, 9)<BR>\n" );
document.write( " C) No x-intercepts, (0, -9)<BR>\n" );
document.write( " D) No x-intercepts, (0, 9)<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #152187 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=152187\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  Find the x- and y-intercepts. If no x-intercepts exist, state so. <BR>\n" );
document.write( "f(x) = 15x^2 - 20x - 9<BR>\n" );
document.write( "A) ((20 (+or-) sqrt 940)/(2)) , (0, -9)<BR>\n" );
document.write( "B) ((20 (+or-) sqrt 940)/(2)) , (0, 9)<BR>\n" );
document.write( "C) No x-intercepts, (0, -9)<BR>\n" );
document.write( "D) No x-intercepts, (0, 9)<BR>\n" );
document.write( "--------------------------<BR>\n" );
document.write( "To find the y-intercept, set x=0. --> y = -9, so it's (0,-9)<BR>\n" );
document.write( "The answer is B or D.<BR>\n" );
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document.write( "For the x-intercepts:<BR>\n" );
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document.write( " <TR><TD  ALIGN=MIDDLE>Solved by <A  rel=nofollow HREF=http://wiki.algebra.com/index.php/Tutoring_-_pluggable_solvers>pluggable</A> solver: <A  rel=nofollow HREF=solve_quadratic_equation.solver>SOLVE quadratic equation (work shown, graph etc)</A></TD></TR>\n" );
document.write( "<TR><TD  ALIGN=LEFT>Quadratic equation <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ax%5E2%2Bbx%2Bc=0 ALIGN=MIDDLE  ALT=\"ax%5E2%2Bbx%2Bc=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > (in our case <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15x%5E2%2B-20x%2B-9+=+0 ALIGN=MIDDLE  ALT=\"15x%5E2%2B-20x%2B-9+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >) has the following solutons:<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca ALIGN=MIDDLE  ALT=\"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "  <BR>\n" );
document.write( "  For these solutions to exist, the <U>discriminant</U> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%5E2-4ac ALIGN=MIDDLE  ALT=\"b%5E2-4ac\"   DISABLED_style= \"max-width:90%; height:auto;\" > should not be a negative number.<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  First, we need to compute the discriminant <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%5E2-4ac ALIGN=MIDDLE  ALT=\"b%5E2-4ac\"   DISABLED_style= \"max-width:90%; height:auto;\" >: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%5E2-4ac=%28-20%29%5E2-4%2A15%2A-9=940 ALIGN=MIDDLE  ALT=\"b%5E2-4ac=%28-20%29%5E2-4%2A15%2A-9=940\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  Discriminant d=940 is greater than zero. That means that there are two solutions: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+x%5B12%5D+=+%28--20%2B-sqrt%28+940+%29%29%2F2%5Ca ALIGN=MIDDLE  ALT=\"+x%5B12%5D+=+%28--20%2B-sqrt%28+940+%29%29%2F2%5Ca\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "  <BR>\n" );
document.write( "    <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5B1%5D+=+%28-%28-20%29%2Bsqrt%28+940+%29%29%2F2%5C15+=+1.68864731445039 ALIGN=MIDDLE  ALT=\"x%5B1%5D+=+%28-%28-20%29%2Bsqrt%28+940+%29%29%2F2%5C15+=+1.68864731445039\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "    <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5B2%5D+=+%28-%28-20%29-sqrt%28+940+%29%29%2F2%5C15+=+-0.355313981117059 ALIGN=MIDDLE  ALT=\"x%5B2%5D+=+%28-%28-20%29-sqrt%28+940+%29%29%2F2%5C15+=+-0.355313981117059\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "    <BR>\n" );
document.write( "    Quadratic expression <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15x%5E2%2B-20x%2B-9 ALIGN=MIDDLE  ALT=\"15x%5E2%2B-20x%2B-9\"   DISABLED_style= \"max-width:90%; height:auto;\" > can be factored:<BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15x%5E2%2B-20x%2B-9+=+%28x-1.68864731445039%29%2A%28x--0.355313981117059%29 ALIGN=MIDDLE  ALT=\"15x%5E2%2B-20x%2B-9+=+%28x-1.68864731445039%29%2A%28x--0.355313981117059%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "  Again, the answer is: 1.68864731445039, -0.355313981117059.\n" );
document.write( "Here's your graph:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+15%2Ax%5E2%2B-20%2Ax%2B-9+%29 ALIGN=MIDDLE  ALT=\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+15%2Ax%5E2%2B-20%2Ax%2B-9+%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ></TD></TR>\n" );
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document.write( "(20 +/-sqrt(940))/30<BR>\n" );
document.write( "= (10 +/-sqrt(235))/15<BR>\n" );
document.write( "None of the above.<BR>\n" );
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document.write( "</TD></TR></TABLE>\n" );