The normal xy graph consists of a horizontal line that represents the x axis and a perpendicular line that runs through the middle of the x axis which represents the y axis. Where the two intersect is given a designation of 0,0. One of the most important relationships of the xy graph is the line called the "slope" or angle of the line from the center point. Finding the y value is easy if you know the slope of the line and the x coordinate.
Review the equation for the slope of a line. The equation for finding the slope is: m = [y1 - y2] / [x1 - x2]. If you know x, you can solve for y to find the y value for the slope of the line.
Define your variables. Graph a line with the following equation: y = -(2/3)x + 3.
Choose any variable for x along the line. Say you choose 3. If x = 3, then y = -2 (( 2/3 )(3) – 4 = 2 – 4).
About the Author
Working as a full-time freelance writer/editor for the past two years, Bradley James Bryant has over 1500 publications on eHow, LIVESTRONG.com and other sites. She has worked for JPMorganChase, SunTrust Investment Bank, Intel Corporation and Harvard University. Bryant has a Master of Business Administration with a concentration in finance from Florida A&M University.