Question

Write an equation for this parabola. The vertex is ( 1, 3)

Answer 1

`a(x - 4)(x + 2) = \\ a {x}^(2) - 2ax - 8a`
so put x=1 solve

`a - 2a - 8a = 3 > > > - 9a = 3 \\ a = ( - 1)/(3)`
then

`( - 1)/(3) {x}^(2) + (2)/(3) + (8)/(3)`