document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=652348>Question 652348</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 91z+30z^2-30 factored completely  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #407966 by </B><A HREF=/tutors/aboutme.mpl?userid=Shana-D77><B>Shana-D77(132)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Shana-D77><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=Shana-D77><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=407966\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> It's best to rearrange this to 30z^2 + 91z - 30  (Az^2 + Bz + C)\r<BR>\n" );
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document.write( "First, multiply A*C  (30*-30 = 900)<BR>\n" );
document.write( "Ask \"What two numbers multiply to get -900 that add to get B (91)?\"<BR>\n" );
document.write( "Answer: 100*-9 (trial and error)<BR>\n" );
document.write( "Rewrite B using the pair you just found: <BR>\n" );
document.write( "30z^2 + 91z - 30<BR>\n" );
document.write( "30z^2 + 100z - 9z - 30<BR>\n" );
document.write( "Parenthesize:<BR>\n" );
document.write( "(30z^2 + 100z) - (9z - 30)<BR>\n" );
document.write( "Factor each parenthesis:<BR>\n" );
document.write( "10z(3z + 10) - 3(3z + 10)  <<- the parenthesis will always be the same.  The first one is always right.<BR>\n" );
document.write( "Rewrite: One () is the stuff on the inside once, the other () is the stuff on the outside:<BR>\n" );
document.write( "(3z + 10)(10z - 3) </SPAN>\n" );
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