Answer:
We know that the equation of a parabola, given the vertex is:
y-yv = a(x-xv)²
with yv being the x of the vertex and yv the y.
So:
y + 2 = a(x + 7)²
We also know it passes through a point, that will satisfy the parabola's equation:
0 + 2 = a(-3 + 7)²
a = 1/8
y = 1/8 (x + 7)² - 2