Aparabola has a vertex at (-1, 0) and opens down. what is the equation of the parabola?

y = -x 2 - 1

Equation for parabola is y = a(x-h)^2 +k, (h, k) is the vertex of the parabola

plug in vertex (-1, 0) h = -1 and k = 0

y = a ( x - (-1))^2 + 0

y = a (x+1)^2   now plug in the values of x and y to find a.

once you have a, plug it into the equation y = (x + 1)^2

i could not follow the values for x and y posted in the problem.