Let the tangent to the curve $x^2+2 x-4 y+9=0$ at the point P(1, 3) on it meet the y-axis at A. Let the line passing through P and parallel to the line x - 3y = 6 meet the parabola $y^2$ = 4x at B. If B lies on the line 2x - 3y = 8. then $(AB)^2$ is equal to
