document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=104632>Question 104632</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0618250182/algebrahomeworkh>Algebra I</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> This is from 4.7 Challenge:  Skills and Applications<BR>\n" );
document.write( "Questions 5 & 6\r<BR>\n" );
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document.write( "In 1992, 7.6 million music videos were shipped and in 1996, 16.9 million were shipped.\r<BR>\n" );
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document.write( "Write an equation you can solve to find the year that the model predicts 25 million music videos will be shipped.\r<BR>\n" );
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document.write( "Then solve the equation graphically.  Interpret the result.\r<BR>\n" );
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document.write( "Things I know:  rate of change is 2.325 million per year.<BR>\n" );
document.write( "Tried this equation:<BR>\n" );
document.write( "25 =2.325x +7.6   (knowing all numbers in millions)<BR>\n" );
document.write( "so to graph I got y=2.325x - 17.4<BR>\n" );
document.write( "but now I have a negative graph and I know that is wrong.\r<BR>\n" );
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document.write( "So I am thinking what I got is x=years later, not the year.  How do I get the year in one equation instead of 2?\r<BR>\n" );
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document.write( "Thanks for any help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #76150 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=76150\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In 1992, 7.6 million music videos were shipped and in 1996, 16.9 million were shipped. <BR>\n" );
document.write( "Write an equation you can solve to find the year that the model predicts 25 million music videos will be shipped. <BR>\n" );
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document.write( "You have two points: (2, 7.6) and (6, 16.9)<BR>\n" );
document.write( "slope = [16.9-7.6]/[6-2] = 2.325<BR>\n" );
document.write( "-----------------<BR>\n" );
document.write( "Equation form is # of videos = 2.325(year) + b<BR>\n" );
document.write( "Nedd to solve for \"b\":<BR>\n" );
document.write( "7.6 = 2.325*2 + b <BR>\n" );
document.write( "7.6 = 4.65 + b<BR>\n" );
document.write( "b = 7.6-4.65 <BR>\n" );
document.write( "b = -2.95<BR>\n" );
document.write( "---------------<BR>\n" );
document.write( "EQUATION:<BR>\n" );
document.write( "# of videos = 2.325(year) - 2.95<BR>\n" );
document.write( "-----------------<BR>\n" );
document.write( "find the year that the model predicts 25 million music videos will be shipped. <BR>\n" );
document.write( "25 = 2.325(year) - 2.95<BR>\n" );
document.write( "27.95 = 2.325(year)<BR>\n" );
document.write( "year = 12.02...<BR>\n" );
document.write( "The year will be 1990+12 = 2002<BR>\n" );
document.write( "==================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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