Final answer:
The quadratic equation for a parabola with specified y-intercept, x-intercepts, and vertex is expressed in factored form as y = (x+7)(x-3), in vertex form as y = (x+2)^2-25, and the standard form is completed correctly as y = x² + 4x - 21.
Step-by-step explanation:
The quadratic equation for a parabola with a y-intercept at (0, -21), x-intercepts at (-7, 0) and (3, 0), and a vertex at (-2,-25) can be written in different forms. Given the information, the factored form, vertex form, and standard form of the equation are as follows:
- Factored form: y = (x + 7)(x - 3)
- Vertex form: y = (x + 2)^2 - 25
- Standard form: y = x² + 4x - 21
Now, let's fill in the blanks in the forms provided in the question using the given intercepts and vertex:
- Factored form: y = (x+7)(x-3)
- Vertex form: y = (x+2)^2-25
- Standard form was already filled correctly as y = x² + 4x-21