document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=410826>Question 410826</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am solving a quadratic equation.  I think I have done it right, but I am not sure how to write the final answer.  Would you please check my work?\r<BR>\n" );
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document.write( "5x^2+22=-10x\r<BR>\n" );
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document.write( "    +10x  -10x+10x<BR>\n" );
document.write( "5x^2+22+10x=0<BR>\n" );
document.write( " a    c  b\r<BR>\n" );
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document.write( "-10+-sqrt((10)^2-4(5)(22)/2(5)<BR>\n" );
document.write( "-10+-sqrt(100-(-440))/(10)<BR>\n" );
document.write( "-10+-sqrt(500)/(10)<BR>\n" );
document.write( "-10+-sqrt(5(100))/(10)<BR>\n" );
document.write( "-10+-10sqrt(5)/(10)<BR>\n" );
document.write( "1+-sqrt(5)/(1)<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 #288813 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=288813\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Not quite. You have a sign error in the following steps:\r<BR>\n" );
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document.write( "-10+-sqrt((10)^2-4(5)(22)/2(5)<BR>\n" );
document.write( "-10+-sqrt(100-(-440))/(10)   <--- should be 100 - 440, not 100 - (-440). Also, 100 - (-440) = 540, not 500.\r<BR>\n" );
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document.write( "By the quadratic formula, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-10+%2B-+sqrt%28100+-+440%29%29%2F10+=+%28-10+%2B-+sqrt%28-340%29%29%2F10 ALIGN=MIDDLE  ALT=\"x+=+%28-10+%2B-+sqrt%28100+-+440%29%29%2F10+=+%28-10+%2B-+sqrt%28-340%29%29%2F10\"   DISABLED_style= \"max-width:90%; height:auto;\" >. We can factor 4 out of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28-340%29 ALIGN=MIDDLE  ALT=\"sqrt%28-340%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > to obtain <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2sqrt%28-85%29 ALIGN=MIDDLE  ALT=\"2sqrt%28-85%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >. This becomes\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-10+%2B-+2sqrt%28-85%29%29%2F10+=+%28-5+%2B-sqrt%28-85%29%29%2F5+=+%28-5+%2B-+i%2Asqrt%2885%29%29%2F5 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "In addition, it is more conventional (and less likely to make a mistake) to write the quadratic as <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5x%5E2+%2B+10x+%2B+22 ALIGN=MIDDLE  ALT=\"5x%5E2+%2B+10x+%2B+22\"   DISABLED_style= \"max-width:90%; height:auto;\" > instead of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5x%5E2+%2B+22+%2B+10x ALIGN=MIDDLE  ALT=\"5x%5E2+%2B+22+%2B+10x\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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