Question

What is the discriminant and minimum value for `y= 3x^2 - 12x - 36`?

Answer 1

`y = 3x^2 - 12x - 36`

Explanation:

`D = d^2 = b^2 - 4ac = 144 + 432 = 576 = 24^2`

Since a > o, the parabola opens upward, there is a minimum at vertex.
x-coordinate of vertex: `x = -b/(2a) = 12/6 = 2`
y-coordinate of vertex: y = f(2) = 12 - 24 - 36 = - 48