Answer:
x = a(y+17)^2 + 2 where a < 0
Explanation:
Since the parabola is horizontal, the formula of the parabola is x = a(y-h)^2 + k where (h,k) is the vertex.
Since it opens to the left, a must be negative. The vertex is (-17, 2), so h = -17 and k = 2.
Substituting these in, we find that the equation is
x = a(y+17)^2 + 2 where a is a real number that is less than 0 (i.e. negative)
I hope this helps! :)