document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=76260>Question 76260</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find a value for k so that 9m(squared)- kn(squared) will have the factors 3m + 7n and 3m - 7n.\r<BR>\n" );
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document.write( "thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #54743 by </B><A HREF=/tutors/aboutme.mpl?userid=wodkit02><B>wodkit02(9)</B></A><img src=\"/images/stars/stars-05.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=wodkit02><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=54743\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If you want the expression to have the factors of (3m-7n) and (3m+7n), you must multiply those factors together to see if it has the form 9m^2-kn^2.\r<BR>\n" );
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document.write( "Using the FOIL method, we get:<BR>\n" );
document.write( "(3m-7n)(3m+7n)<BR>\n" );
document.write( "9m^2+10m-10m-49n^2<BR>\n" );
document.write( "9m^2-49n^2\r<BR>\n" );
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document.write( "Now we compare this result to the expression with the k-value in it:<BR>\n" );
document.write( "9m^2-kn^2 = 9m^2-49n^2\r<BR>\n" );
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document.write( "thus k = 49 </SPAN>\n" );
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