The equation for a parabola can also be written in the "vertex form":
x = a (y - h) ^ 2 + k
In this equation, the vertex of the parabola is the point (h, k).
We have then:
x = y2 + 6y + 1
We look for the vertice:
0 = 2y + 6
y = -6 / 2
y = -3
Substituting:
x = (-3) ^ 2 + 6 (-3) +1
x = -8
Substituting the vertice point:
x = (y + 3) ^ 2 - 8
Answer:
x = (y + 3) ^ 2 - 8
option C