Janna behanihe invented it
A function z=f(x,y) has two partial derivatives and y. These derivatives correspond to each of the independent variables and can be interpreted as instantaneous rates of change (that is, as slopes of a tangent line). Similarly, ∂z/∂y represents the slope of the tangent line parallel to the y-axis.
The slope is -4.
Because:
-8/2 is -4, which is the slope.
120 is the answer I’m not first but that’s alright