Answer:
y = (x + 3)^2 - 6.
Explanation:
The vertex formula is Y = a(x - h)^2 + k.
To find the vertex formula, we need to find h and k, by finding the vertex of x^2 + 6x + 3.
h = -b/2a
a = 1, b = 6.
h = -6 / 2 * 1 = -6 / 2 = -3
k = (-3)^2 + 6(-3) + 3 = 9 - 18 + 3 = -9 + 3 = -6
So far, we have Y = a(x - (-3))^2 + -6, so y = a(x + 3)^2 - 6.
In this case, the coefficient of x^2 of the given formula is 1, which means that a will be 1.
The vertex form of x^2 + 6x + 3 is y = (x + 3)^2 - 6.
To check our work...
y = (x + 3)^2 - 6
= x^2 + 3x + 3x + 9 - 6
= x^2 + 6x + 3
Hope this helps!