7 The equation of a curve is
$$x ^ { 2 } + y ^ { 2 } - 4 x y + 3 = 0$$
- Show that \(\frac { \mathrm { d } y } { \mathrm {~d} x } = \frac { 2 y - x } { y - 2 x }\).
- Find the coordinates of each of the points on the curve where the tangent is parallel to the \(x\)-axis.