What do a, B and C represent in quadratic function Their meaning in quadratic function

What do a, B and C represent in quadratic function Their meaning in quadratic function

They are quadratic coefficient, linear coefficient and constant term
A represents the opening direction of quadratic function. If a is greater than 0, the opening is upward. If a is less than 0, the opening is downward
A and B represent the axis of symmetry of quadratic function. When a and B have the same sign, the axis of symmetry is on the left side of Y axis, and when a and B have different sign, it is on the right side of Y axis
C represents the ordinate (0, c) of the image of quadratic function and the focus of y-axis
ABC determines △ at the same time, that is, whether the function image has a focus on the X axis and the number of focuses

About quadratic function, can you tell me what the letters in quadratic function expression represent?

General formula: F (x) = ax ^ 2 + BX + C (A0) a: positive function image opening up, negative function image opening down - B / 2A: function image symmetry axis (4ac-b ^ 2) / 4A: function maximum (image vertex ordinate) C: function image longitudinal intercept (f (0)) vertex formula: F (x) = a (x-m) ^ 2 + n (A0) a: positive function image opening to

If the coordinates of point a are (- 3,0) B are (1,0) C are (0, - 2), how to use the intersection of quadratic function to find the parabola expression?

Let the quadratic function be y = a (x + 3) (x-1), and substitute (0, - 2) into - 2 = a * 3 * (- 1), so a = 2 / 3, so y = 2 / 3 (x + 3) (x-1)