document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=130039>Question 130039</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/003052217x/algebrahomeworkh>Algebra 1</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> I need to verify whether each equation is an identity or not by substituting -1, 0, and 1 for X.\r<BR>\n" );
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document.write( "Lesson 9.4 extra practice in the back of the book.\r<BR>\n" );
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document.write( "Problem #7.      x^+4x+3=(x+1)(x+3) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #94986 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=94986\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2B4x%2B3=%28x%2B1%29%28x%2B3%29 ALIGN=MIDDLE  ALT=\"x%5E2%2B4x%2B3=%28x%2B1%29%28x%2B3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Start with the given equation\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-1%29%5E2%2B4%28-1%29%2B3=%28-1%2B1%29%28-1%2B3%29 ALIGN=MIDDLE  ALT=\"%28-1%29%5E2%2B4%28-1%29%2B3=%28-1%2B1%29%28-1%2B3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Plug in <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=-1 ALIGN=MIDDLE  ALT=\"x=-1\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2B4%28-1%29%2B3=%28-1%2B1%29%28-1%2B3%29 ALIGN=MIDDLE  ALT=\"1%2B4%28-1%29%2B3=%28-1%2B1%29%28-1%2B3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Square -1 to get 1\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1-4%2B3=%28-1%2B1%29%28-1%2B3%29 ALIGN=MIDDLE  ALT=\"1-4%2B3=%28-1%2B1%29%28-1%2B3%29\"   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=0=%280%29%282%29 ALIGN=MIDDLE  ALT=\"0=%280%29%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Combine like terms\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0=0 ALIGN=MIDDLE  ALT=\"0=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply. So the solution <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=-1 ALIGN=MIDDLE  ALT=\"x=-1\"   DISABLED_style= \"max-width:90%; height:auto;\" > works\r<BR>\n" );
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document.write( "------------------------\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2B4x%2B3=%28x%2B1%29%28x%2B3%29 ALIGN=MIDDLE  ALT=\"x%5E2%2B4x%2B3=%28x%2B1%29%28x%2B3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Start with the given equation\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%280%29%5E2%2B4%280%29%2B3=%280%2B1%29%280%2B3%29 ALIGN=MIDDLE  ALT=\"%280%29%5E2%2B4%280%29%2B3=%280%2B1%29%280%2B3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Plug in <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=0 ALIGN=MIDDLE  ALT=\"x=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0%2B4%280%29%2B3=%280%2B1%29%280%2B3%29 ALIGN=MIDDLE  ALT=\"0%2B4%280%29%2B3=%280%2B1%29%280%2B3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Square 0 to get 0\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0%2B0%2B3=%280%2B1%29%280%2B3%29 ALIGN=MIDDLE  ALT=\"0%2B0%2B3=%280%2B1%29%280%2B3%29\"   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=3=%281%29%283%29 ALIGN=MIDDLE  ALT=\"3=%281%29%283%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Combine like terms\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3=3 ALIGN=MIDDLE  ALT=\"3=3\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply. So the solution <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=0 ALIGN=MIDDLE  ALT=\"x=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > works\r<BR>\n" );
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document.write( "---------------------------\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2B4x%2B3=%28x%2B1%29%28x%2B3%29 ALIGN=MIDDLE  ALT=\"x%5E2%2B4x%2B3=%28x%2B1%29%28x%2B3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Start with the given equation\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%29%5E2%2B4%281%29%2B3=%281%2B1%29%281%2B3%29 ALIGN=MIDDLE  ALT=\"%281%29%5E2%2B4%281%29%2B3=%281%2B1%29%281%2B3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Plug in <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=1 ALIGN=MIDDLE  ALT=\"x=1\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2B4%281%29%2B3=%281%2B1%29%281%2B3%29 ALIGN=MIDDLE  ALT=\"1%2B4%281%29%2B3=%281%2B1%29%281%2B3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Square -1 to get 1\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2B4%2B3=%281%2B1%29%281%2B3%29 ALIGN=MIDDLE  ALT=\"1%2B4%2B3=%281%2B1%29%281%2B3%29\"   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=%282%29%284%29 ALIGN=MIDDLE  ALT=\"8=%282%29%284%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Combine like terms\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8=8 ALIGN=MIDDLE  ALT=\"8=8\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply. So the solution <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=1 ALIGN=MIDDLE  ALT=\"x=1\"   DISABLED_style= \"max-width:90%; height:auto;\" > works\r<BR>\n" );
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document.write( "Since more than one solution works, this equation is an identity\r<BR>\n" );
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document.write( "Note:\r<BR>\n" );
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document.write( "Another way you can prove that the equation is an identity is to foil the right side and simplify. </SPAN>\n" );
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