document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1114738>Question 1114738</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 20.\r<BR>\n" );
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document.write( "Suppose that income is a function of age. The following function represents the relation between average annual income l and age a.<BR>\n" );
document.write( " l(a)=-55a^2+5117a-54,421\r<BR>\n" );
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document.write( "(A) For what age does average income l equal $40,000?<BR>\n" );
document.write( "(B) For what age does average income l equal $60,000?\r<BR>\n" );
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document.write( "(a) Average income l is equal $40,000 for the age of? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #729661 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=729661\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> For part (A)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-55a%5E2%2B5117a-54421=40000 ALIGN=MIDDLE  ALT=\"-55a%5E2%2B5117a-54421=40000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-55a%5E2%2B5117a-94421=0 ALIGN=MIDDLE  ALT=\"-55a%5E2%2B5117a-94421=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "General solution for quadratic equation:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=%28-5117%2B-+sqrt%285117%5E2-4%2A%28-55%2A%28-94421%29%29%29%2F%28-2%2A55%29 ALIGN=MIDDLE  ALT=\"a=%28-5117%2B-+sqrt%285117%5E2-4%2A%28-55%2A%28-94421%29%29%29%2F%28-2%2A55%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=%28-5117%2B-+sqrt%285117%5E2-4%2A55%2A94421%29%29%2F%28-2%2A55%29 ALIGN=MIDDLE  ALT=\"a=%28-5117%2B-+sqrt%285117%5E2-4%2A55%2A94421%29%29%2F%28-2%2A55%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=%285117%2B-+sqrt%285117%5E2-4%2A55%2A94421%29%29%2F%282%2A55%29 ALIGN=MIDDLE  ALT=\"a=%285117%2B-+sqrt%285117%5E2-4%2A55%2A94421%29%29%2F%282%2A55%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=%285117%2B-+sqrt%285411069%29%29%2F%282%2A55%29 ALIGN=MIDDLE  ALT=\"a=%285117%2B-+sqrt%285411069%29%29%2F%282%2A55%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Compute this and take the value which makes sense. </SPAN>\n" );
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