It is known that the vertex coordinates of the image of the quadratic function y = x2 + BX + C are (1, - 4), and the intersection point with the Y axis is a.1. Find the relationship of the quadratic function and the point a coordinates (3) If two non coincident points whose coordinates are (m, n) and (n, m) are on the image of the quadratic function, the value of M + n is obtained (4) If the quadratic function intersects with the negative half axis of X axis at point B, C is a point on the function image, D is a point on X axis, when the quadrilateral with a, B, C, D as the vertex is a parallelogram, please write the area of the parallelogram directly The key is the fourth question~

It is known that the vertex coordinates of the image of the quadratic function y = x2 + BX + C are (1, - 4), and the intersection point with the Y axis is a.1. Find the relationship of the quadratic function and the point a coordinates (3) If two non coincident points whose coordinates are (m, n) and (n, m) are on the image of the quadratic function, the value of M + n is obtained (4) If the quadratic function intersects with the negative half axis of X axis at point B, C is a point on the function image, D is a point on X axis, when the quadrilateral with a, B, C, D as the vertex is a parallelogram, please write the area of the parallelogram directly The key is the fourth question~

1) At the time of x = 0, y = -3 {a (0, - 3) 3) n = m \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\x = 3  B (- 1,0) C