4 The equation of a curve \(C\) is \(y = 2 x ^ { 2 } - 8 x + 9\) and the equation of a line \(L\) is \(x + y = 3\).
- Find the \(x\)-coordinates of the points of intersection of \(L\) and \(C\).
- Show that one of these points is also the stationary point of \(C\).