Question

write the equation of the quadratic function with roots -2 and 4 and a vertex at (1,9)

Answer 1

@primeralph

Answer 2

so... where do you think the parabola is going towards? upwards or downwards?

Answer 3

right, up wards?

Answer 4

the roots, so-called, are where the graph TOUCHES the x-axis, or x-intercepts

notice the vertex is up above both... so .. anyhow

the vertex form of a parabola is http://www.mathwarehouse.com/geometry/parabola/images/standard-vertex-forms.png