document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=444986>Question 444986</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need a little help with this graphing question. Honestly, I just don't get graphs very well. Also, if you wouldn't mind showing your work, so that I will understand how you arrived to the answer. Thank you!\r<BR>\n" );
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document.write( "Homework question:<BR>\n" );
document.write( "The graph below shows the price change of an item over several years. Find the rate at which the price is increasing. <BR>\n" );
document.write( "http://www.flickr.com/photos/62474130@N03/5687847434/\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #306633 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=306633\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The slope of a linear function measure <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=the ALIGN=MIDDLE  ALT=\"the\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+rate ALIGN=MIDDLE  ALT=\"+rate\"   DISABLED_style= \"max-width:90%; height:auto;\" > of increase per unit. For straight lines, the rate of change (slope) is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=constant ALIGN=MIDDLE  ALT=\"constant\"   DISABLED_style= \"max-width:90%; height:auto;\" > (always the same).  \r<BR>\n" );
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document.write( "so, you have two points on your graph and you need to calculate a slope <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m ALIGN=MIDDLE  ALT=\"m\"   DISABLED_style= \"max-width:90%; height:auto;\" >:\r<BR>\n" );
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document.write( "(3,40) and (7, 210)\r<BR>\n" );
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document.write( "slope <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m=%28y2-y1%29%2F%28x2-x1%29 ALIGN=MIDDLE  ALT=\"m=%28y2-y1%29%2F%28x2-x1%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=m=%28210-40%29%2F%287-3%29 ALIGN=MIDDLE  ALT=\"m=%28210-40%29%2F%287-3%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=m=170%2F4 ALIGN=MIDDLE  ALT=\"m=170%2F4\"   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=m=42.5 ALIGN=MIDDLE  ALT=\"m=42.5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Intercept is found from equation <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=mx1%2Bb=y1 ALIGN=MIDDLE  ALT=\"mx1%2Bb=y1\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3m%2Bb=40 ALIGN=MIDDLE  ALT=\"3m%2Bb=40\"   DISABLED_style= \"max-width:90%; height:auto;\" >. <BR>\n" );
document.write( "From that,<BR>\n" );
document.write( "intercept <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b ALIGN=MIDDLE  ALT=\"b\"   DISABLED_style= \"max-width:90%; height:auto;\" > is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b=y1-3m=40-3%2A42.5=40-127.5=87.5 ALIGN=MIDDLE  ALT=\"b=y1-3m=40-3%2A42.5=40-127.5=87.5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "so, equation of this line is:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=+42.5x+%2B+87.5 ALIGN=MIDDLE  ALT=\"y=+42.5x+%2B+87.5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "so,  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=the ALIGN=MIDDLE  ALT=\"the\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+rate ALIGN=MIDDLE  ALT=\"+rate\"   DISABLED_style= \"max-width:90%; height:auto;\" > of increase  is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=42.5 ALIGN=MIDDLE  ALT=\"42.5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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