document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=29716>Question 29716</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Assume that all variables represent real numbers. Indicate whether each equation determines y to be a function of x.<BR>\n" );
document.write( "                                              y - 2x = 0<BR>\n" );
document.write( "Can you help me understand the concept of finding the answer? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #16616 by </B><A HREF=/tutors/aboutme.mpl?userid=sdmmadam@yahoo.com><B>sdmmadam@yahoo.com(530)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=sdmmadam@yahoo.com><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=16616\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> y - 2x = 0  ----(1)<BR>\n" );
document.write( "y = 2x is of the form y=(m)x which represents a line <BR>\n" );
document.write( "through the origin with slope = 2<BR>\n" );
document.write( "Let us now plot points after drawing the preliminary rectangular co-ordinate axes of reference(the x-axis andthe y axis) and marking the point O,the origin, giving values to x say:   <BR>\n" );
document.write( "-4,-3,-2.5,-2,-1.5,-1,0,1,2,3,3.5,4,4.5,5,5.5,6 etc<BR>\n" );
document.write( "we get the corresponding values of y given by<BR>\n" );
document.write( "-8,-6,-5,-4,-3,-2,0,1,4,6,7,8,9,10,11,12, ...<BR>\n" );
document.write( "we get points (-4,-8),(-3,-6),(-2.5,-5),(-2,-4),(-1.5,-3),(-1,-2),(0,0),(1,2),(2,4),(3,6),(3.5,7),(4,8),(4.5,9),(5,10),(5.5,11),(6,12)..<BR>\n" );
document.write( "which when plotted and joined by a smooth line we get a line through the origin. If we measure the angle which this line makes with the positive side of the x-axis and consider the trigonometric function tangent of this angle which by definition is the slope of the line we get the value 2. </SPAN>\n" );
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