Question

How do you write `y =2x^2 - 5x - 6` in vertex form?

Answer 1

`y = 2(x - 5/4)^2 - 73/8`

Explanation:

`y = 2x^2 - 5x - 6`
x-coordinate of vertex:
`x = -b/(2a) = 5/4`
y-coordinate of vertex:
`y(5/4) = 2(25/16) - 5(5/4) - 6 = - 25/8 - 48/8 = - 73/8`
Vertex `(5/4, -73/8)`
Vertex form of y:
`y = 2(x - 5/4)^2 - 73/8`
graph{2x^2 - 5x - 6 [-20, 20, -10, 10]}