document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=75699>Question 75699</A>: <I><SPAN STYLE=\"word-break: break-all;\"> can some help me simplify this?\r<BR>\n" );
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document.write( "x^2+2x-80 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #54369 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=54369\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Simplify:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2B2x-80 ALIGN=MIDDLE  ALT=\"x%5E2%2B2x-80\"   DISABLED_style= \"max-width:90%; height:auto;\" > This trinomial can be factored.<BR>\n" );
document.write( "The factors will take the form: (x+m)(x+n) where m and n must meet the follwing restrictions:<BR>\n" );
document.write( "m*n = -80 and <BR>\n" );
document.write( "m+n = 2<BR>\n" );
document.write( "How do we know this?<BR>\n" );
document.write( "Well, when you multiply the two factors, you should get back the original trinomial, right? Right!...so, usinf FOIL:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x%2Bm%29%28x%2Bn%29+=+x%5E2%2Bnx%2Bmx%2Bnm ALIGN=MIDDLE  ALT=\"%28x%2Bm%29%28x%2Bn%29+=+x%5E2%2Bnx%2Bmx%2Bnm\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2B%28m%2Bn%29x%2Bm%2An ALIGN=MIDDLE  ALT=\"x%5E2%2B%28m%2Bn%29x%2Bm%2An\"   DISABLED_style= \"max-width:90%; height:auto;\" > and if you compare this with the original trinomial, you can see that:<BR>\n" );
document.write( "m+n = 2 and <BR>\n" );
document.write( "m*n = -80<BR>\n" );
document.write( "Since the sum of m and n is quite small (2), this would indicate that the absolute values of m and n are are very close to each other.<BR>\n" );
document.write( "A wise choice would be:<BR>\n" );
document.write( "m = 10 and n = -8 or<BR>\n" );
document.write( "m = -10 and n = 8<BR>\n" );
document.write( "because both of their products are -80.<BR>\n" );
document.write( "Select the pair whose sum is 2, that has to be m = 10 and n = -8.<BR>\n" );
document.write( "So, now you can write:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2B2x-80+=+%28x%2B10%29%28x-8%29 ALIGN=MIDDLE  ALT=\"x%5E2%2B2x-80+=+%28x%2B10%29%28x-8%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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