What is the vertex of 2x2 plus 4x?

Answer 1

We know that the x-coordinate of the vertex is x = -b/2a.

We identify a, b, and c in f(x) = ax^2 + bx + c.

y = 2x^2 + 4x or y = 2x^2 + 4x + 0

a = 2, b = 4, c = 0

Substitute 2 for a and 4 for b into the x-coordinate equation:

x = -b/2a = -4/2(2) = -4/4 = -1

So the x-coordinate of the vertex is -1.

To find the y-coordinate, substitute -1 for x in the equation of the function, y = 2x^2 + 4x.

y = 2x^2 + 4x = 2(-1)^2 + 4(-1) = 2 - 4 = -2.

Thus, the vertex is (-1, -2).