The slope-intercept form of a linear equation is y = mx + b. In this equation, m is the slope of the line, and b is the y-intercept, which is the point where the line crosses the y-axis.
The equation of a line allows the identification of the coordinates of any point on that line. For example, if the equation of a line is given as y = 2x + 6, then all coordinate points that fall on that line have x and y values that satisfy the equation. If the x-coordinate of a point is 1, then y = 2(1) + 6, or 8, so the point (1, 8) must be on the line defined by y = 2x + 6.