document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1067007>Question 1067007</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help please!\r<BR>\n" );
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document.write( "Use technology to find the quadratic regression curve through the given points. HINT [See Example 5.] (Round all coefficients to four decimal places.)\r<BR>\n" );
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document.write( "{(0, 1), (-2, 7), (-4, 4)}\r<BR>\n" );
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document.write( "y(x)= \r<BR>\n" );
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document.write( "Im so confused please help </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #682272 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=682272\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \"Example 5\" may give you a clue that I do not have.<BR>\n" );
document.write( "Not having your textbook, or class notes (and not knowing your teacher/instructor),<BR>\n" );
document.write( "I can only guess what answer is expected. My guess would be as follows.<BR>\n" );
document.write( "I would use Microsoft Excel<BR>\n" );
document.write( "(because that is the technology I have handy).<BR>\n" );
document.write( "I assume you have Microsoft Office or at least Excel in your computer.<BR>\n" );
document.write( "I would enter the x values (0,-2,-4) on column A,<BR>\n" );
document.write( "and the y value corresponding to each x to its right, on column B.<BR>\n" );
document.write( "Unfortunately, software like Excel is continuously updated,<BR>\n" );
document.write( "so that you may encounter different versions on different computers.<BR>\n" );
document.write( "The commands needed and the way results are displayed<BR>\n" );
document.write( "change a little from one version to the next.<BR>\n" );
document.write( "In my version of Excel,<BR>\n" );
document.write( "I have to click on the Insert tab,<BR>\n" );
document.write( "to be able to graph the regression curve.<BR>\n" );
document.write( "I can do that before or after<BR>\n" );
document.write( "selecting (highlighting) the data I had entered.<BR>\n" );
document.write( "Then, with the data highlighted,<BR>\n" );
document.write( "I would select \"scatter\" as my chart type choice,<BR>\n" );
document.write( "and the graph choice with only points (no line).<BR>\n" );
document.write( "A graph with the points plotted would appear.<BR>\n" );
document.write( "Right-clicking on one of the points on that graph,<BR>\n" );
document.write( "would make a menu pop up,<BR>\n" );
document.write( "and I would click on \"Add Trendline\".<BR>\n" );
document.write( "That would make another menu window pop up,<BR>\n" );
document.write( "where I would select \"Polynomial\" with order 2,<BR>\n" );
document.write( "and \"Display Equation on chart\",<BR>\n" );
document.write( "before hitting \"close.\"<BR>\n" );
document.write( "Right-clicking on the equation that appears on the graph,<BR>\n" );
document.write( "I would select \"Format Trendline Label\",<BR>\n" );
document.write( "and then four the option number kon the left side),<BR>\n" );
document.write( "I would choose \"Number\" and 4 decimal places,<BR>\n" );
document.write( "before hitting close.<BR>\n" );
document.write( "The equation on the graph would read<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-1.1250x%5E2-5.2500x%2B%221.0000%22 ALIGN=MIDDLE  ALT=\"y=-1.1250x%5E2-5.2500x%2B%221.0000%22\"   DISABLED_style= \"max-width:90%; height:auto;\" > ,<BR>\n" );
document.write( "and that is the answer I guess would be expected.<BR>\n" );
document.write( " <BR>\n" );
document.write( "NOTE 1: Excel is not the only technology available,<BR>\n" );
document.write( "and in your class another kind of software,<BR>\n" );
document.write( "or maybe a graphing calculator could be the technology<BR>\n" );
document.write( "that you were expected to use.<BR>\n" );
document.write( "NOTE 2: Technology is not needed for this particular problem,<BR>\n" );
document.write( "because the curve represents scented by that equation<BR>\n" );
document.write( "passes exactly through those three points.<BR>\n" );
document.write( "Just like two points determine a line,<BR>\n" );
document.write( "Three points determine a quadratic function.<BR>\n" );
document.write( "So, you could have<BR>\n" );
document.write( "written <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=ax%5E2%2Bbx%2Bc ALIGN=MIDDLE  ALT=\"y=ax%5E2%2Bbx%2Bc\"   DISABLED_style= \"max-width:90%; height:auto;\" > and<BR>\n" );
document.write( "substituted the coordinates of the three points,<BR>\n" );
document.write( "to get a system of 3 linear equations on a, b, and c,<BR>\n" );
document.write( "whose solution would give you the answer.<BR>\n" );
document.write( "If you had been given more than three points,<BR>\n" );
document.write( "It could be that no quadratic line would go through all points.<BR>\n" );
document.write( "Then, technology would be the best way to find the<BR>\n" );
document.write( "\"best fit\" regression curve. </SPAN>\n" );
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