In algebra, the point-slope form of an equation for a line is written as y - y1 = m(x - x1). The variables y1 and x1 equal the values of the given point, and m equals the slope.
The slope is calculated by using two points on the line to find the change in y over the change in x. The slope is also based on the expression rise over run where the vertical change is divided by the horizontal change. The equation is called slope-intercept form because it is calculated with the value of the slope and value of a single point on the line, which can be used to find the y-intercept.