Final answer:
To find y'(3) for the ellipse equation

, we implicitly differentiate and solve for y'. The answer is y'(3) = -3/(4√7).
Step-by-step explanation:
The equation

represents an ellipse. To find y'(3), we need to implicitly differentiate the given equation with respect to x. Let's perform the differentiation:
Differentiate both sides with respect to x: 2x/16 + 2yy'/64 = 0.
- Simplify and solve for y': y' = -x/(2y).
- Substitute x = 3 and y = 2√7 into the equation for y': y'(3) = -3/(4√7).
The value of y' at x = 3 is -3/(4√7).