Math Help - implicit differentiation

1. implicit differentiation

2. $-4x^{2} - 4xy - 3y^{3} = -192$

Taking the derivative of both sides:

$-8x - 4(y + xy') - 9y^{2}y' = 0$

The middle term -4(y + xy') is just using the product rule in differentiating.

Solve for y' at (-4,4) and that will be your slope value.

You should be able to go from there?