Answer:
4
Step by step:
This is if the question is saying you completed 87.5% of the exercises. Otherwise, I don't know what it is asking.
87.5% of 32=28
32-28=4
When x=-1:

Ok that gives us a little more information.
If we implicitly differentiate with respect to t, from the very start, then we can apply our product rule, ya?

The right side is zero, derivative of a constant is zero.
Where x' is dx/dt and y' is dy/dt.
From here, plug in all the stuff you know:
y' = -3
x = -1
y = 4
and solve for x'.
Hope that helps!
Answer: C Hope it's helpful