document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=256939>Question 256939</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Good afternoon. I need some help with this problem.\r<BR>\n" );
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document.write( "This is under the title of solving polynomial equations.\r<BR>\n" );
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document.write( "Solve (x+3)*(x-3)= 40. Identify any double roots.\r<BR>\n" );
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document.write( "I've tried different methods\r<BR>\n" );
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document.write( "(x+3)*(x-3)=40    =   x^2-9=40 = Answer {7,-7}<BR>\n" );
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document.write( "(x+3)*(x+3)+40=0<BR>\n" );
document.write( "40(x+3)*(x-3)=0<BR>\n" );
document.write( "40(x^2-9)=0<BR>\n" );
document.write( "5(x-3)*8(x+3)=0<BR>\n" );
document.write( "Answer: {3, -3}\r<BR>\n" );
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document.write( "or \r<BR>\n" );
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document.write( "(x+3)*(x-3)=40<BR>\n" );
document.write( "(7+3)*(-7-3)=40<BR>\n" );
document.write( "-70=40<BR>\n" );
document.write( "Answer {0,3,-3}\r<BR>\n" );
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document.write( "I'm really confused so any help is welcome thank you. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #188991 by </B><A HREF=/tutors/aboutme.mpl?userid=drk><B>drk(1908)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=drk><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=188991\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Here is the original equation<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x%2B3%29%2A%28x-3%29=+40 ALIGN=MIDDLE  ALT=\"%28x%2B3%29%2A%28x-3%29=+40\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "step 1 - foil the left side to get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+-+9+=+40 ALIGN=MIDDLE  ALT=\"x%5E2+-+9+=+40\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "step 2 - add 9 to get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+=+49 ALIGN=MIDDLE  ALT=\"x%5E2+=+49\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "step 3 - take a square root to get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=7 ALIGN=MIDDLE  ALT=\"x=7\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=-7 ALIGN=MIDDLE  ALT=\"x=-7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "In this case there are no double roots.<BR>\n" );
document.write( "--<BR>\n" );
document.write( "to check let x = 7 and we get<BR>\n" );
document.write( "(7+3)(7-3) = 40 - - - > 10*4 = 40 = 40 [true]<BR>\n" );
document.write( "Now let x = -7<BR>\n" );
document.write( "(-7+3)(-7-3) = 40 - - > (-4)(-10) = 40  = 40 [true] </SPAN>\n" );
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