Work Step by Step
If the vertex of a graph is at (m,n), then the general formula for the quadratic function is $f(x)=a(x-m)^2+n$. The vertex of the graph is at (-3,1), hence the quadratic function becomes $f(x)=a(x+3)^2+1$. The point (0,-8) is on the graph, hence if we plug in the values we get -8=9a+1, a=-1. $f(x)=-(x+3)^2+1$.