Dodi has 2 cups of liquid starch and will use the entire amount. she plans to store the slime in containers that each hold a maximum of 6 fluids ounces. how many containers will she need?

The slope of the line that passes through two points is

(the difference in 'y') divided by (the difference in 'x').

The two points are:  (3, -4) and (5, -7)

The difference in 'y' is . . . (-7) - (-4) = -3

The difference in 'x' is . . . (5) - (3) = 2

The slope of the line through those two points is (-3) / (2) .

That's the 3rd choice on the list.