Explanation:
it looks like the line goes through (7, 6) and through (8, -2).
the slope of a line is the ratio of y/x. it indicates how many units y changes, when x changes a certain amount of units.
so, for our 2 points we see x changes only by +1 unit (from 7 to 8 : 8 - 7 = 1). at the same time y changes by -8 units (from 6 to -2 : -2 - 6 = -8).
therefore, or slope is y/x = -8/1 = -8