1. **State the problem:**
We have a curve $C$ defined by the implicit equation
$$x^3 + 2xy - x - y^3 - 20 = 0$$
We are given the derivative expression
$$\frac{dy}{dx} = \frac{3x^2 + 2y - 1}{3y^2 - 2x}$$
We need to find the equation of the tangent line to the curve at the point $(3, -2)$ in the form $ax + by + c = 0$ where $a,b,c$ are integers.
2. **Find the slope of the tangent line at $(3,-2)$:**
Substitute $x=3$ and $y=-2$ into the derivative formula:
$$\frac{dy}{dx} = \frac{3(3)^2 + 2(-2) - 1}{3(-2)^2 - 2(3)} = \frac{3 \times 9 - 4 - 1}{3 \times 4 - 6} = \frac{27 - 4 - 1}{12 - 6} = \frac{22}{6}$$
Simplify the fraction:
$$\frac{22}{6} = \frac{\cancel{2} \times 11}{\cancel{2} \times 3} = \frac{11}{3}$$
So the slope $m = \frac{11}{3}$.
3. **Write the tangent line equation using point-slope form:**
The point-slope form is
$$y - y_1 = m(x - x_1)$$
Substitute $m=\frac{11}{3}$ and point $(3,-2)$:
$$y - (-2) = \frac{11}{3}(x - 3)$$
$$y + 2 = \frac{11}{3}x - 11$$
4. **Rewrite in standard form $ax + by + c = 0$ with integer coefficients:**
Multiply both sides by 3 to clear the denominator:
$$3(y + 2) = 11x - 33$$
$$3y + 6 = 11x - 33$$
Bring all terms to one side:
$$11x - 3y - 33 - 6 = 0$$
$$11x - 3y - 39 = 0$$
5. **Final answer:**
The equation of the tangent line is
$$11x - 3y - 39 = 0$$
This is in the form $ax + by + c = 0$ with $a=11$, $b=-3$, and $c=-39$.
Tangent Line Ae2440
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