Parabola Vertex: Finding the Center

I can determine the vertex of a parabola by completing the square.

6:14

We don't generate video — this one is by Khan Academy on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.

1. 1

   The vertex form of a quadratic equation is y = A(x - B)² + C, where the vertex of the parabola is the point (B, C).

2. 2

   To complete the square, factor out the coefficient of the x² term, then add and subtract (b/2)² inside the parentheses to create a perfect square trinomial.

3. 3

   After completing the square and simplifying, the x-coordinate of the vertex is the value that makes the squared term equal to 0, and the y-coordinate is the constant term in the vertex form.

“Determine the vertex of the parabola y = 2x² + 8x - 3 using either the formula x = -b/2a or by completing the square. Show all your steps.”

Sample answer included in the free materials