document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=244895>Question 244895</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello<BR>\n" );
document.write( "I have a function f(x) represented graphically, but the function f(x) is unknown. All i know is several values of f(x) at the corresponding x. How can i identify the expression of the function? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #179038 by </B><A HREF=/tutors/aboutme.mpl?userid=jsmallt9><B>jsmallt9(3758)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jsmallt9><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=179038\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> It would help if you could share these coordinates with us.<br><BR>\n" );
document.write( "Is the graph a recognizable shape? A line? A parabola? Other?<br><BR>\n" );
document.write( "If it is a line, then we need to find the slope. The slope can be found using the slope formula:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+%28y%5B2%5D+-+y%5B1%5D%29%2F%28x%5B2%5D+-+x%5B1%5D%29 ALIGN=MIDDLE  ALT=\"m+=+%28y%5B2%5D+-+y%5B1%5D%29%2F%28x%5B2%5D+-+x%5B1%5D%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Then use the slope and one of the points to find the equation of the line.<br><BR>\n" );
document.write( "In case your graph is a line, here's an example using the points (5, 8) and (6, -3):<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+%28-3+-+8%29%2F%286+-+5%29 ALIGN=MIDDLE  ALT=\"m+=+%28-3+-+8%29%2F%286+-+5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m+=+%28-11%29%2F1+=+-11 ALIGN=MIDDLE  ALT=\"m+=+%28-11%29%2F1+=+-11\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now we use the slope and either point to find the equation. There are a couple of ways to do this:<ul><li>Using the Slope-intercept form</li><li>Using the Point-Slope form.</li></ul><BR>\n" );
document.write( "Since the form of the equation of a line that is a function is the Slope-intercept form, I'll use that method so save a couple fo steps:<BR>\n" );
document.write( "Slope-intercept form: y = mx + b<BR>\n" );
document.write( "Use the slope and a point to find b:<BR>\n" );
document.write( "8 = -11(5) + b<BR>\n" );
document.write( "8 = -55 + b<BR>\n" );
document.write( "63 = b<BR>\n" );
document.write( "Write the equation using m and b:<BR>\n" );
document.write( "y = -11x + 63<BR>\n" );
document.write( "Rewrite it using functional notation:<BR>\n" );
document.write( "f(x) = -11x + 63<br><BR>\n" );
document.write( "If the graph is not the graph of a line, then finding the equation is more difficult.<BR>\n" );
document.write( " </SPAN>\n" );
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