The quadratic function g(x) has a vertex at (-5, 0) and y-intercept of (0, -5). What is g(1)?
I have no idea how to do this.
you are given the vertex of the quadratic, so that should be telling you that you can use vertex form of the quadratic.
the vertex form of g(x) can be written as
a(x-h)^2 + k where the vertex is (h,k)
g(x) = a(x+5)^2
since it has a y intercept of 5, the point (0,-5) should lie on this graph as well
-5 = a(5)^2 = 25a
a = -1/5
now we have our function:
g(x) = -1/5(x+5)^2
g(1) = -36/5