document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=997727>Question 997727</A>: <I><SPAN STYLE=\"word-break: break-all;\"> solve\r<BR>\n" );
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document.write( "the proper pH of the water in swimming pools is 7.4 + or - 0.2. Write an absolute value inequality representing this range. Then solve the inequality to state the range of the pH.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #615693 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=615693\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let x represent the ph of the water.\r<BR>\n" );
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document.write( "|x - 7.4| <= .2\r<BR>\n" );
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document.write( "when (x - 7.4) is positve, the equation becomes (x - 7.4) <= .2 which results in x <= 7.6\r<BR>\n" );
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document.write( "when (x - 7.4) is negative, the equation becomes (x - 7.4) >= -.2 which results in x >= 7.2\r<BR>\n" );
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document.write( "you reverse the inequality and you change the sign of the expression on the right when (x - 7.4) is negative.\r<BR>\n" );
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document.write( "there's a valid reason for doing this that i won't get into unless you ask.<BR>\n" );
document.write( "it involves the basic definition of absolute value.\r<BR>\n" );
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document.write( "you get x <= 7.6 and x >= 7.4.\r<BR>\n" );
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document.write( "this can be written as 7.4 <= x <= 7.6\r<BR>\n" );
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document.write( "this means that the ph is good if it reads from 7.4 to 7.6 and not good otherwise.\r<BR>\n" );
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