document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=24019>Question 24019</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve this: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2=5%28x%2B4%29 ALIGN=MIDDLE  ALT=\"x%5E2=5%28x%2B4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > please give me a step by step solution. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #12729 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=12729\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+=+5%28x%2B4%29 ALIGN=MIDDLE  ALT=\"x%5E2+=+5%28x%2B4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > this is saying where does the straight line, y=5(x+4) cross (ie is EQUAL TO) the curve y = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2 ALIGN=MIDDLE  ALT=\"x%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >. This is difficult to solve as it stands and you would have to plot it on a graph and then your answer may not be a precise answer depending upon how good you were are drawing curves etc.\r<BR>\n" );
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document.write( "However, combining the 2 equations into one is easy, as follows:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+=+5%28x%2B4%29 ALIGN=MIDDLE  ALT=\"x%5E2+=+5%28x%2B4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+=+5x%2B20 ALIGN=MIDDLE  ALT=\"x%5E2+=+5x%2B20\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+-+5x+-+20+=+0 ALIGN=MIDDLE  ALT=\"x%5E2+-+5x+-+20+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Now we have one equation, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+x%5E2+-+5x+-+20 ALIGN=MIDDLE  ALT=\"y+=+x%5E2+-+5x+-+20\"   DISABLED_style= \"max-width:90%; height:auto;\" > and we need to know where this crosses the x-axis, namely y=0. This is much better to solve, since we do not need to plot a graph. We can do it mathematically and arrive at the precise answer(s).\r<BR>\n" );
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document.write( "So... method is to factorise, hopefully. If not, then use the quadratic formula. I can see no obvious factorisation, so quadratic formula it is:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-b+%2B-+sqrt%28b%5E2-4ac%29%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"x+=+%28-b+%2B-+sqrt%28b%5E2-4ac%29%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-%28-5%29+%2B-+sqrt%28%28-5%29%5E2-4%281%29%28-20%29%29%29%2F%282%281%29%29 ALIGN=MIDDLE  ALT=\"x+=+%28-%28-5%29+%2B-+sqrt%28%28-5%29%5E2-4%281%29%28-20%29%29%29%2F%282%281%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%285+%2B-+sqrt%2825%2B80%29%29%2F2 ALIGN=MIDDLE  ALT=\"x+=+%285+%2B-+sqrt%2825%2B80%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%285+%2B-+sqrt%28105%29%29%2F2 ALIGN=MIDDLE  ALT=\"x+=+%285+%2B-+sqrt%28105%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%285+%2B+sqrt%28105%29%29%2F2 ALIGN=MIDDLE  ALT=\"x+=+%285+%2B+sqrt%28105%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%285+-+sqrt%28105%29%29%2F2 ALIGN=MIDDLE  ALT=\"x+=+%285+-+sqrt%28105%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "These are the 2 precise answers. You can use a calculator but you will have to round up the answers it gives you, thus being approximate answers.\r<BR>\n" );
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document.write( "jon.<BR>\n" );
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