document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=425052>Question 425052</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The formula y=2.6sqrtX +9 models the percent of U.S. adults who are considered obese by federal guidelines, where X is the number of years after 1980, and Y is the percent of obese adults. In this equation, Y is already converted from a decimal, so, for example, a 55% obesity rate would correspond to Y=55.\r<BR>\n" );
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document.write( "According to this formula, in what year was the obesity rate 15.4 percent?\r<BR>\n" );
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document.write( "Answer: In the year  <BR>\n" );
document.write( "Round to the nearest actual year. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #296109 by </B><A HREF=/tutors/aboutme.mpl?userid=htmentor><B>htmentor(1343)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=htmentor><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=htmentor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=296109\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Set y = 15.4 and solve for x:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15.4+=+2.6%2Asqrt%28x%29+%2B+9 ALIGN=MIDDLE  ALT=\"15.4+=+2.6%2Asqrt%28x%29+%2B+9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Subtract 9 from RHS, divide by 2.6 and square both sides:<BR>\n" );
document.write( "(6.4/2.6)^2 = x = 6.059 years after 1980.<BR>\n" );
document.write( "Therefore, the year was 1986. </SPAN>\n" );
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