document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=103520>Question 103520</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Could someone please remind me how to solve this equation. Factor completely.<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15x%5E2%2B8x-16 ALIGN=MIDDLE  ALT=\"15x%5E2%2B8x-16\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #75258 by </B><A HREF=/tutors/aboutme.mpl?userid=oberobic><B>oberobic(2304)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=oberobic><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=75258\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You can approach this by trial and error. First, consider what the factors of 15 are:  either 3*5 or 1*15. The factors of 16 are either 4*4 or 2*8 or 1*16. So, you will have factoring like:<BR>\n" );
document.write( "(3x +/- 2)(5x +/- 8)<BR>\n" );
document.write( "(3x +/- 4)(5x +/- 4)<BR>\n" );
document.write( "etc.<BR>\n" );
document.write( "Note that the -16 tells us that one of the factors has a + and the other has a -. Also, we know that the +x's will out number the -x's by 8 (i.e., the middle term is +8x.<BR>\n" );
document.write( "By trial and error:<BR>\n" );
document.write( "(3x + 4)(5x - 4) = 15x^2 - 12x + 20x - 16 = 15x^2 + 8x - 16.<BR>\n" );
document.write( "Well, what luck!  Found it on the first try!<BR>\n" );
document.write( "The factors are (3x+4)(5x-4). </SPAN>\n" );
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