Step-by-step explanation:
the slope of a line is the ratio y/x.
that means, when going from one point to the other, how many units y changes, when x changes a certain number of units.
the sign indicates the direction of the change (+ for larger and - for smaller).
so, here x changes by 6 units (from -3 to 3), and y changes by -2 units (from 4 to 2).
therefore, the slope is
-2/6 = -1/3
