document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=821615>Question 821615</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Let G(v) be a linear function representing the grade point average of a high school student who plays video games for v minutes a day. When a student plays video games for 85 minutes a day, the student's grade point average is 2.89. When a student plays video games for 155 minutes a day, the student's grade point average is 2.05. \r<BR>\n" );
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document.write( "a. Determine the formula for the linear function G(v). \r<BR>\n" );
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document.write( "b. Give a practical interpretation of the slope in terms of grade point average and amount of time spent playing video games.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #494285 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=494285\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Plot <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+v+ ALIGN=MIDDLE  ALT=\"+v+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = min/day on the horizontal axis<BR>\n" );
document.write( "Plot <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+G%28v%29+ ALIGN=MIDDLE  ALT=\"+G%28v%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = GPA on the vertical axis<BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "You are given 2 points on the line:<BR>\n" );
document.write( "( 85, 2.85 ) and<BR>\n" );
document.write( "( 155, 2.05 )<BR>\n" );
document.write( "------------<BR>\n" );
document.write( "Use the general point-slope formula:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+G+-+2.05+%29+%2F+%28+v+-+155+%29+=+%28+2.85+-+2.05+%29+%2F+%28+85+-+155+%29+ ALIGN=MIDDLE  ALT=\"+%28+G+-+2.05+%29+%2F+%28+v+-+155+%29+=+%28+2.85+-+2.05+%29+%2F+%28+85+-+155+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+G+-+2.05+%29+%2F+%28+v+-+155+%29+=+.8+%2F+%28+-70+%29+ ALIGN=MIDDLE  ALT=\"+%28+G+-+2.05+%29+%2F+%28+v+-+155+%29+=+.8+%2F+%28+-70+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+G+-+2.05+%29+%2F+%28+v+-+155+%29+=+-8%2F700+ ALIGN=MIDDLE  ALT=\"+%28+G+-+2.05+%29+%2F+%28+v+-+155+%29+=+-8%2F700+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+G+-+2.05+=+%28+-8%2F700+%29%2A%28+v+-+155+%29+ ALIGN=MIDDLE  ALT=\"+G+-+2.05+=+%28+-8%2F700+%29%2A%28+v+-+155+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+700%2A%28+G+-+2.05+%29+=+-8%2A%28+v+-+155+%29+ ALIGN=MIDDLE  ALT=\"+700%2A%28+G+-+2.05+%29+=+-8%2A%28+v+-+155+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+700G+-+1435+=+-8v+%2B+1240+ ALIGN=MIDDLE  ALT=\"+700G+-+1435+=+-8v+%2B+1240+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+700G+=+-8v+%2B+2675+ ALIGN=MIDDLE  ALT=\"+700G+=+-8v+%2B+2675+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+G+=+-.0114v+%2B+3.821+ ALIGN=MIDDLE  ALT=\"+G+=+-.0114v+%2B+3.821+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "-------------------------<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "does it go through ( 85,2.85 )?<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+G+=+-.0114v+%2B+3.821+ ALIGN=MIDDLE  ALT=\"+G+=+-.0114v+%2B+3.821+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+2.85+=+-.0114%2A85+%2B+3.821+ ALIGN=MIDDLE  ALT=\"+2.85+=+-.0114%2A85+%2B+3.821+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+2.85+=+-.969+%2B+3.821+ ALIGN=MIDDLE  ALT=\"+2.85+=+-.969+%2B+3.821+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+2.85+=+2.852+ ALIGN=MIDDLE  ALT=\"+2.85+=+2.852+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "( error due to rounding off? )<BR>\n" );
document.write( "You can test the other point<BR>\n" );
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document.write( "(b)<BR>\n" );
document.write( "The slope is the drop in GPA for each additional minute<BR>\n" );
document.write( "played on video games<BR>\n" );
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document.write( "Here's the plot:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+400%2C+400%2C+-20%2C+350%2C+-1%2C+5%2C+-.0114x+%2B3.821+%29+ ALIGN=MIDDLE  ALT=\"+graph%28+400%2C+400%2C+-20%2C+350%2C+-1%2C+5%2C+-.0114x+%2B3.821+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "As you can see, if you play about 6 hours a day,<BR>\n" );
document.write( "your GPA drops to zero\r<BR>\n" );
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document.write( " </SPAN>\n" );
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