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:
See below.
Step-by-step explanation:
It transforms to the Pythagoras theorem.
c^2 = a^2 + b^2 - 2ab cos C
If C = 90, cos C = zero so the last term disappears.
c^2 = a^2 + b^2 - 2ab * 0
c^2 = a^2 + b^2.
I think that it the secound one then the fourth one then the sixth one then the first one then the fifth one then third one the eighth one then the ninth one
The answer is 5.9% I think because you have to round up if it’s 5 and above