Question

Write y = 2x^2 + 8x + 3 in vertex form.

y = 2(x – 2)^2 – 5


y = (x – 4)^2 + 3


y = 2(x + 2)^2 – 5


y = (x + 4)^2 + 3

Answer 1

y = 2(x + 2)^2 – 5

Explanation:

When y = ax^2 +bx +c is written in vertex form, it becomes ...

y = a(x +b/(2a))^2 +(c -b^2/(4a))

The constant term in the squared binomial is b/(2a) = 8/(2(2)) = +2. Only one answer choice matches:

y = 2(x +2)^2 -5