document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=177981>Question 177981</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find a value for k that will make 4x^2 + 6.4 x + k a perfect square. Describe the procedure that you used which requires algebra [that is, not trial and error].   \r<BR>\n" );
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document.write( "been on this 1 for awhile just can't find the appropiate equation to make it work. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #132984 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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/cgi-bin/show-face.mpl?user=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=132984\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Times New Roman\" size=\"+2\">\r<BR>\n" );
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document.write( "Find <i>k</i> such that <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large 4x^2 + 6.4 x + k\"> is a perfect square.\r<BR>\n" );
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document.write( "Factor out the 4:  <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large 4(x^2 + 1.6 x + \frac {k}{4})\"> \r<BR>\n" );
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document.write( "Divide the coefficient on the <i>x</i> term by 2 and square the result:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large (\frac {1.6}{2})^2 = (0.8)^2 = 0.64\">\r<BR>\n" );
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document.write( "Now we know that <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \frac {k}{4} = 0.64\">\r<BR>\n" );
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document.write( "Hence: <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large k = 2.56\">\r<BR>\n" );
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document.write( "</font> </SPAN>\n" );
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