document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=41165>Question 41165</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I don't quite understand this one.\r<BR>\n" );
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document.write( "Find a value for  k   so that   9m^2  - kn^2  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 #26683 by </B><A HREF=/tutors/aboutme.mpl?userid=vidhyak><B>vidhyak(98)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vidhyak><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=26683\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find a value for  k   so that   9m^2  - kn^2  will have the factors  3m + 7n, and 3m - 7n.\r<BR>\n" );
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document.write( "(a + b)(a-b) = a^2 - b^2\r<BR>\n" );
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document.write( "The factors are 3m + 7n, and 3m - 7n. Let's apply the above formula <BR>\n" );
document.write( "a = 3m and b = 7n\r<BR>\n" );
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document.write( "(3m + 7n)(3m - 7n) = 9m^2 - 49n^2\r<BR>\n" );
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document.write( "Comparing 9m^2 - 49n^2 with  9m^2  - kn^2, we get k = 49 </SPAN>\n" );
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