8 The equation of a curve is
$$x ^ { 2 } + 2 x y - y ^ { 2 } + 8 = 0$$
- Show that the tangent to the curve at the point \(( - 2,2 )\) is parallel to the \(x\)-axis.
- Find the equation of the tangent to the curve at the other point on the curve for which \(x = - 2\), giving your answer in the form \(y = m x + c\).