Question

Write the equation of the quadratic function with roots -10 and -8 and a vertex at (-9, -3).

Answer 1

Shelbs,
if -10 and -8 are roots of a quadratic function
then f(x)=a(x+10)(x+8)

Answer 2

that gives you and idea of what the function could be
you only need to use the vertex to find out the rest