document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=997019>Question 997019</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The amount of a particular pollutant p from a power plant in the air above the plant depends on the wind speed s, among other things, with the relationship between p and s approximated by p=16-0.04s^2, with s in miles per hour.<BR>\n" );
document.write( "a) find the value(s) of s that will make p=0<BR>\n" );
document.write( "b)what does p=0 mean in this application?<BR>\n" );
document.write( "c)what solution to 0=16-0.04s^2 makes sense in the context of this application? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #615282 by </B><A HREF=/tutors/aboutme.mpl?userid=addingup><B>addingup(3677)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=addingup><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=addingup><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=615282\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve for s:<BR>\n" );
document.write( "0= 16-0.04s^2 Now, .04 is the same as 1/25 (do the math). So, rewrite:<BR>\n" );
document.write( "16-0.04 s^2= 16-s^2/25:<BR>\n" );
document.write( "0= 16-s^2/25 Let's flip the equation to make it more elegant:<BR>\n" );
document.write( "16-s^2/25= 0<BR>\n" );
document.write( "The left hand side factors into a product with four terms:<BR>\n" );
document.write( "-1/25((s-20)(s+20))= 0 Multiply both sides by -25 (and -25*0= 0)<BR>\n" );
document.write( "(s-20) (s+20) = 0<BR>\n" );
document.write( "Split into two equations:<BR>\n" );
document.write( "s-20 = 0 or s+20 = 0<BR>\n" );
document.write( "Add 20 to both sides:<BR>\n" );
document.write( "s = 20 or s+20 = 0<BR>\n" );
document.write( "Subtract 20 from both sides:<BR>\n" );
document.write( "s = 20 or s = -20<BR>\n" );
document.write( "Since s is squared, both numbers give you the same result: 20*20=400 and -20*-20 also= 400. However, we are measuring the amount of a pollutant p in the air so the number we are looking for has to be 0 or higher. Therefore, 20 is your answer.<BR>\n" );
document.write( "Proof: <BR>\n" );
document.write( "16-0.04(20)^2= 0<BR>\n" );
document.write( "16-0.04(400)= 0<BR>\n" );
document.write( "16-16= 0 We have the correct answer<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );