## Intermediate Algebra for College Students (7th Edition)

The vertex of $x=a(y-k)^2+h$ is at $(h,k)$. The vertex of $y=a(x-k)^2+h$ is at $(k,h)$. a) $y$ is squared, thus the parabola is horizontal b) the coefficient of $y^2$ is negative, thus the parabola opens to the left c) the vertex is at $(4,-1)$.