document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1140035>Question 1140035</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A person's systolic blood pressure, which is measured in millimeters of mercury (mm Hg), depends on a person's age, in years. The equation:\r<BR>\n" );
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document.write( "P=0.005y2−0.01y+119P=0.005y2-0.01y+119\r<BR>\n" );
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document.write( "gives a person's blood pressure, <BR>\n" );
document.write( "P<BR>\n" );
document.write( "P<BR>\n" );
document.write( ", at age <BR>\n" );
document.write( "y<BR>\n" );
document.write( "y<BR>\n" );
document.write( "years.\r<BR>\n" );
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document.write( "A.) Find the systolic pressure, to the nearest tenth of a millimeter, for a person of age 40 years.\r<BR>\n" );
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document.write( "B.) If a person's systolic pressure is 131 mm Hg, what is their age (rounded to the nearest whole year)? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #760540 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=760540\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> substitute 40 for y<BR>\n" );
document.write( "0.005*1600=8<BR>\n" );
document.write( "-0.01*40=-0.4<BR>\n" );
document.write( "+119<BR>\n" );
document.write( "126.6\r<BR>\n" );
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document.write( "for the other it is 131=0.005y^2-0.01y+119<BR>\n" );
document.write( "or 0.005y^2-0.01y-12=0<BR>\n" );
document.write( "multiply by 200to clear decimals<BR>\n" );
document.write( "y^2-2y-2400=0<BR>\n" );
document.write( "y=(1/2)(2+ sqrt(4+9600))<BR>\n" );
document.write( "=50 years old<BR>\n" );
document.write( " </SPAN>\n" );
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