document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=147759>Question 147759</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0764584677/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> (2z+5)(4z-10z+25) \r<BR>\n" );
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document.write( "The 4z is supposed to be squared but I can't figure out how to type that on here.  \r<BR>\n" );
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document.write( "The portion of the chapter where this problem is found is called Creating the Sum and Difference of Cubes.  It gives you a short cut for finding the solution, but does not give any detail to help me figure out how they reached the answer.  I can not except the solution they want me to give without knowing what is done to reach that answer.  They give the solution in the end of the chapter and I understand why the first and last terms are what they are, but can not figure out why the middle term disappears.  Please help!   </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #108135 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=108135\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%282z%2B5%29%284z%5E2-10z%2B25%29 ALIGN=MIDDLE  ALT=\"%282z%2B5%29%284z%5E2-10z%2B25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Start with the given expression.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2z%284z%5E2-10z%2B25%29%2B5%284z%5E2-10z%2B25%29 ALIGN=MIDDLE  ALT=\"2z%284z%5E2-10z%2B25%29%2B5%284z%5E2-10z%2B25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Expand.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%282z%29%2A%284z%5E2%29%2B%282z%29%2A%28-10z%29%2B%282z%29%2A%2825%29%2B%285%29%2A%284z%5E2%29%2B%285%29%2A%28-10z%29%2B%285%29%2A%2825%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" > Distribute.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8%2Az%5E3-20%2Az%5E2%2B50%2Az%2B20%2Az%5E2-50%2Az%2B125 ALIGN=MIDDLE  ALT=\"8%2Az%5E3-20%2Az%5E2%2B50%2Az%2B20%2Az%5E2-50%2Az%2B125\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8%2Az%5E3%2B125 ALIGN=MIDDLE  ALT=\"8%2Az%5E3%2B125\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now combine like terms.\r<BR>\n" );
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document.write( "Notice how <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8%2Az%5E3%2B125 ALIGN=MIDDLE  ALT=\"8%2Az%5E3%2B125\"   DISABLED_style= \"max-width:90%; height:auto;\" > is a binomial where both terms are cubes of other terms. In other words, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8%2Az%5E3=%282z%29%5E3 ALIGN=MIDDLE  ALT=\"8%2Az%5E3=%282z%29%5E3\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=125=%285%29%5E3 ALIGN=MIDDLE  ALT=\"125=%285%29%5E3\"   DISABLED_style= \"max-width:90%; height:auto;\" >. The short cut you mentioned would use the sum of cubes formula <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%5E3%2BB%5E3=%28A%2BB%29%28A%5E2-AB%2BB%5E2%29 ALIGN=MIDDLE  ALT=\"A%5E3%2BB%5E3=%28A%2BB%29%28A%5E2-AB%2BB%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > to expand the original problem (which is a much faster way to solve the problem).\r<BR>\n" );
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document.write( "So <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%282z%2B5%29%284z%5E2-10z%2B25%29 ALIGN=MIDDLE  ALT=\"%282z%2B5%29%284z%5E2-10z%2B25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > expands to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8%2Az%5E3%2B125 ALIGN=MIDDLE  ALT=\"8%2Az%5E3%2B125\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
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document.write( "In other words, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%282z%2B5%29%284z%5E2-10z%2B25%29=8%2Az%5E3%2B125 ALIGN=MIDDLE  ALT=\"%282z%2B5%29%284z%5E2-10z%2B25%29=8%2Az%5E3%2B125\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
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