document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=149912>Question 149912</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The stabilization ratio (birth/death)for south and central america can be modeled by the formula y= -0.0012x^2 + 0.074x + 2.69 where y is the number of birth divided by the number of deaths in the year 1950 + x.\r<BR>\n" );
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document.write( "Use the formula to find the year in which the stabilization ratio was at its maximum?<BR>\n" );
document.write( "What was the maximum stabilization ration from above?<BR>\n" );
document.write( "What is the significance of a stabilization ratio of 1? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #110034 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=110034\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The stabilization ratio (birth/death)for south and central America can be modeled by the formula y= -0.0012x^2 + 0.074x + 2.69 where y is the number of birth divided by the number of deaths in the year 1950 + x.<BR>\n" );
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document.write( "Use the formula to find the year in which the stabilization ratio was at its maximum?<BR>\n" );
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document.write( "Find the axis of symmetry of the equation; x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-b%29%2F%282a%29 ALIGN=MIDDLE  ALT=\"%28-b%29%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > a=-.0012; b=.074<BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-.074%29%2F%282%28-.0012%29%29 ALIGN=MIDDLE  ALT=\"%28-.074%29%2F%282%28-.0012%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-.074%29%2F%28-.0024%29 ALIGN=MIDDLE  ALT=\"%28-.074%29%2F%28-.0024%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = 30.83<BR>\n" );
document.write( "Max stability occurred 1950 + 30.83 in 1980, (about October)<BR>\n" );
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document.write( "What was the maximum stabilization equation from above?<BR>\n" );
document.write( "Substitute 30.83 for x in the equation and find y:<BR>\n" );
document.write( "y = -.0012(30.83^2) + .074(30.83) + 2.69<BR>\n" );
document.write( "y = -.0012(950.674) + 2.28 + 2.69<BR>\n" );
document.write( "y = -1.14 + 2.28 + 2.69<BR>\n" );
document.write( "y = 3.83 is the max birth/death ratio<BR>\n" );
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document.write( "What is the significance of a stabilization ratio of 1?<BR>\n" );
document.write( "That would occur when deaths = births </SPAN>\n" );
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