What is the slope of the line between # (-7,11) # and # (-2, -7) #?
y = mx + b Calculate the slope, m, from the given point values, solve for b by using one of the point values, and check your solution using the other point values, if required.
A line can be thought of as the ratio of the change between horizontal (x) and vertical (y) positions. Thus, for any two points defined by Cartesian (planar) coordinates such as those given in this problem, you simply set up the two changes (differences) and then make the ratio to obtain the slope, m.
Vertical difference “y” = y2 – y1 = -7 – 11 = -18
Horizontal difference “x” = x2 – x1 = -2 – -7 = 5
Ratio = “rise over run”, or vertical over horizontal = -18/5 for the slope, m.