Given the vertex of a parabola is (-3,1) and also contains the point (-4,-1). State the exact equation of the parabola in vertex form, show all your work.

Respuesta :

Answer:

y = -2(x + 3)^2 - 1

Step-by-step explanation:

The vertex equation of a parabola is y = a(x - h)^2 + k.  If the vertex here is (-3, 1), then this equation becomes y = a(x + 3)^2 + 1.

Knowing that the graph passes through (-4, -1), we let  y = -1 and x = -4, obtaining:

-1 = a(-4 + 3)^2 - 1, which must be solved for a:

-1 = a - 1.  Therefore, a = -2, and the exact equation of this parabola is:

y = -2(x + 3)^2 - 1