
Above, I changed the fraction form of x and y into exponential form so it is easier to see the differentiation. Now, we can differentiate:

Now that we have dy/dx, we can plug in the x, which is 4, and the y, which is 4/19. We know these values of x and y because your question stated y(4) = 4/19.
3 probably will be the gcf of it.... or maybe 3x^3 y^3 z
Not sure tho
Answer:
(2.5,-0.5)
Step-by-step explanation: