document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=117946>Question 117946</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi, this question is a multiple choice question from the pre-ACT test.  I don't even know where to start with this one, I tried solving for x, and I tried to put the answer choices in the problem, but to no avail.  I believe this is an identity but I can't figure out how to use that knowledge to solve this.  This problem has frustrated me for 2 days.\r<BR>\n" );
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document.write( "In the equation, x^2 + 16x + a = (x + b)^2,  a and b are constants. If the equation is true for all values of x, what is the value of a?\r<BR>\n" );
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document.write( "the answer choices are: 4, 8, 16, 64, or 256.  The correct answer is 64 but I have no idea how to work out the problem to get that answer.  Please help me figure this problem out.<BR>\n" );
document.write( "thanks for your help!  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #85965 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=85965\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Here's one approach you could try.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2B16x%2Ba+=+%28x%2Bb%29%5E2 ALIGN=MIDDLE  ALT=\"x%5E2%2B16x%2Ba+=+%28x%2Bb%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Expand the right side.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2B16x%2Ba+=+x%5E2%2B2bx%2Bb%5E2 ALIGN=MIDDLE  ALT=\"x%5E2%2B16x%2Ba+=+x%5E2%2B2bx%2Bb%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2 ALIGN=MIDDLE  ALT=\"x%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > from both sides.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=16x%2Ba+=+2bx%2Bb%5E2 ALIGN=MIDDLE  ALT=\"16x%2Ba+=+2bx%2Bb%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Now equate the x-terms.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=16x+=+2bx ALIGN=MIDDLE  ALT=\"16x+=+2bx\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide by 2x.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8+=+b ALIGN=MIDDLE  ALT=\"8+=+b\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now equate the constant terms.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+=+b%5E2 ALIGN=MIDDLE  ALT=\"a+=+b%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > but b = 8, so...<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+=+8%5E2 ALIGN=MIDDLE  ALT=\"a+=+8%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and...<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+=+64 ALIGN=MIDDLE  ALT=\"a+=+64\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " </SPAN>\n" );
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