document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=885645>Question 885645</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find the equation, in factored form, of the quadratic function with zeros -3 and -7 that passes through the point (-5, 4) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #535336 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=535336\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> if the zeroes are -3 and -7, you can find the factors by doing the following:\r<BR>\n" );
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document.write( "first zero:<BR>\n" );
document.write( "x = -3<BR>\n" );
document.write( "add 3 to both sides of this equation to get:<BR>\n" );
document.write( "x + 3 = 0\r<BR>\n" );
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document.write( "second zero:<BR>\n" );
document.write( "x = -7<BR>\n" );
document.write( "add 7 to both sides of this equation to get:<BR>\n" );
document.write( "x + 7 = 0\r<BR>\n" );
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document.write( "so far your factors are:<BR>\n" );
document.write( "(x + 3) * (x + 7)\r<BR>\n" );
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document.write( "put these factors into equation form and you get:<BR>\n" );
document.write( "f(x) = (x + 3) * (x + 7)\r<BR>\n" );
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document.write( "since the equation goes through the point (-5,4), then when x = -4 you should get f(x) = -5.\r<BR>\n" );
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document.write( "replacing x with -5, you get f(x) (-5 + 3) * (-5 + 7) which is equal to (-2) * (2) which is equal to (-4).\r<BR>\n" );
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document.write( "this is the right value but the wrong sign.\r<BR>\n" );
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document.write( "what this means is you need another factor of (-1) to make sure you get the right value.\r<BR>\n" );
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document.write( "your factors become:<BR>\n" );
document.write( "f(x) = (-1) * (x + 3) * (x + 7)\r<BR>\n" );
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document.write( "now when you replace x with -5, you get f(x) = (-1) * (-2) * (2) which is equal to (-1) * (-4) which is equal to 4.\r<BR>\n" );
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document.write( "your factors are:<BR>\n" );
document.write( "(-1) * (x + 3) * (x + 7)\r<BR>\n" );
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document.write( " </SPAN>\n" );
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