document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=77222>Question 77222</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help this is confusing to me.<BR>\n" );
document.write( "Find a value for k so tha 9m^2 - kn^2 will have the factors 3m + 7n and 3m - 7n. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #55331 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=55331\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If you foil <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%283m+%2B+7n%29%283m+-+7n%29 ALIGN=MIDDLE  ALT=\"%283m+%2B+7n%29%283m+-+7n%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > you get\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%283m+%2B+7n%29%283m+-+7n%29=9m%5E2%2B21mn-21mn-49n%5E2 ALIGN=MIDDLE  ALT=\"%283m+%2B+7n%29%283m+-+7n%29=9m%5E2%2B21mn-21mn-49n%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%283m+%2B+7n%29%283m+-+7n%29=9m%5E2%2Bcross%2821mn-21mn%29-49n%5E2 ALIGN=MIDDLE  ALT=\"%283m+%2B+7n%29%283m+-+7n%29=9m%5E2%2Bcross%2821mn-21mn%29-49n%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Notice the middle terms cancel\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%283m+%2B+7n%29%283m+-+7n%29=9m%5E2-49n%5E2 ALIGN=MIDDLE  ALT=\"%283m+%2B+7n%29%283m+-+7n%29=9m%5E2-49n%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So we have <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9m%5E2-49n%5E2 ALIGN=MIDDLE  ALT=\"9m%5E2-49n%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > which is equal to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9m%5E2+-+kn%5E2 ALIGN=MIDDLE  ALT=\"9m%5E2+-+kn%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > so in other words:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9m%5E2-49n%5E2=9m%5E2+-+kn%5E2 ALIGN=MIDDLE  ALT=\"9m%5E2-49n%5E2=9m%5E2+-+kn%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-49n%5E2=+-+kn%5E2 ALIGN=MIDDLE  ALT=\"-49n%5E2=+-+kn%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9m%5E2 ALIGN=MIDDLE  ALT=\"9m%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > from both sides\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-49=+-+k ALIGN=MIDDLE  ALT=\"-49=+-+k\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide both sides by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n%5E2 ALIGN=MIDDLE  ALT=\"n%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=49=+k ALIGN=MIDDLE  ALT=\"49=+k\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide both sides by -1\r<BR>\n" );
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document.write( "So we get\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=49 ALIGN=MIDDLE  ALT=\"k=49\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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