Question

A parabola opening up or down has vertex (0,5) and passes through (4,1). Write its equation in vertex form.

Answer 1

see below

Explanation:

y = a ( x-0)^2 + 5 sub in the point given to calculate 'a'

1 = a (4)^2 + 5

-4 = 16a

a = - 1/4

y = -1/4 x^2 + 5