Answer:
the minimum value of y is -324
Explanation:
Add the square of half the g coefficient:
g^2 -2g +1 = y +324
(g -1)^2 -324 = y
This is "vertex form" indicating the vertex is (1, -324). The leading coefficient is positive, so the parabola opens upward. The vertex is the minimum.
Minimum y-value is -324.