Question

Find the vertex of this parabola:
y = -5x2 - 10x - 15
Enter the correct answer.

Answer 1

Vertex of parabola (-1, -10)

Explanation:

For a given quadratic y = ax² + bx + c, the vertex (h, k) is found by computing h = –b/2a, and then evaluating y at h to find k. If you've already learned the Quadratic Formula, you may find it easy to memorize the formula for k, since it is related to both the formula for h and the discriminant in the Quadratic Formula: k = (4ac – b2) / 4a.