document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=207958>Question 207958</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can someone help me with this question?\r<BR>\n" );
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document.write( "In 1995 the United States recovered 23% of its municipal solid wastes through recycling, up from 17% in 1990. Find an equation for the line whose graph depicts this data (where x is measured in years after 1990).  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #157388 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=157388\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> in 1995 23% was recovered.<BR>\n" );
document.write( "in 1990 17% was recovered.<BR>\n" );
document.write( "let z = the year<BR>\n" );
document.write( "let x = z - 1990<BR>\n" );
document.write( "this means that if z is 1990, x = 0<BR>\n" );
document.write( "this also means that if z is 1995, x = 5<BR>\n" );
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document.write( "let y = % recovered.<BR>\n" );
document.write( "on a graph we would plot y from x.<BR>\n" );
document.write( "our 2 points of consideration are:<BR>\n" );
document.write( "(0,17) and (5,23)<BR>\n" );
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document.write( "equation for a straight line is y = mx + b where m is the slope and b is the y intercept.<BR>\n" );
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document.write( "the y intercept is the value of y when x = 0 which will be 17.<BR>\n" );
document.write( "the slope is given by the formula y2-y1 / x2 - x1<BR>\n" );
document.write( "x1,y1 = 0,17<BR>\n" );
document.write( "x2,y2 = 5,23<BR>\n" );
document.write( "y2-y1 = 23 - 17 = 6<BR>\n" );
document.write( "x2  x1 = 5 - 0 = 5<BR>\n" );
document.write( "out slope is 6/5<BR>\n" );
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document.write( "straight line equation becomes y = 6/5 * x + 17<BR>\n" );
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document.write( "graph of this equation looks like this:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28600%2C600%2C-2%2C10%2C-2%2C40%2C%286%2F5%29%2Ax+%2B+17%29 ALIGN=MIDDLE  ALT=\"graph%28600%2C600%2C-2%2C10%2C-2%2C40%2C%286%2F5%29%2Ax+%2B+17%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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