document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=259531>Question 259531</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This is supposed to be review, so I feel kind of stupid, but i forgot how to do point-slope form. Well... here's my problem:\r<BR>\n" );
document.write( "\n" );
document.write( "Write the point-slope form of the equation of the line through the given points.\r<BR>\n" );
document.write( "\n" );
document.write( "Through: (0,-1) and (3,1)\r<BR>\n" );
document.write( "\n" );
document.write( "I have more of these, so I only want one answer so i can know how to do the rest... Thank You!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #191014 by </B><A HREF=/tutors/aboutme.mpl?userid=mathbath><B>mathbath(13)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mathbath><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=191014\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If (x1,y1) and (x2,y2) are any two co-ordinates on the line the slope \"m\" of the line is calculated by, <BR>\n" );
document.write( "m=(y2-y1)/(x2-x1)\r<BR>\n" );
document.write( "\n" );
document.write( "Substituting the values from the given problem..\r<BR>\n" );
document.write( "\n" );
document.write( "(x1,y1) = (0,-1)<BR>\n" );
document.write( "(x2,y2) = (3,1)\r<BR>\n" );
document.write( "\n" );
document.write( "So,<BR>\n" );
document.write( "m = (1 - (-1))/(3 - 0)<BR>\n" );
document.write( "m = (1 + 1)/(3)<BR>\n" );
document.write( "m = 2/3\r<BR>\n" );
document.write( "\n" );
document.write( "Now the standard equation for a straight line is..<BR>\n" );
document.write( "y=mx+c  --> (1)\r<BR>\n" );
document.write( "\n" );
document.write( "where m is the slope<BR>\n" );
document.write( "and c is the y-intercept of the line i.e., when the line hits the y-axis and    x = 0\r<BR>\n" );
document.write( "\n" );
document.write( "If you notice the co-ordinate (0,-1) ..<BR>\n" );
document.write( "x = 0, y = -1<BR>\n" );
document.write( "This is the co-ordinate where the line intersects the y-axis. So our y intercept is -1<BR>\n" );
document.write( "So,<BR>\n" );
document.write( "c = -1<BR>\n" );
document.write( "Substituting the values in (1)\r<BR>\n" );
document.write( "\n" );
document.write( "y = 2/3x - 1 which is the point slope form of the equation  </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );