Find Vertex from Factored Form

Identify the form of the quadratic function:
f(x)=3(x+2)(x-1)

• Quadratic

• Standard

• Factored

• Vertex

Identify the form of the quadratic function:

f(x) = (x - 8)(x + 8)

• Vertex

• Standard

• Factored

Write a quadratic equation given the x intercepts and one other point.

Step 2: Find a.

Now that you know that the factors are (x-6) and (x-8), you must find a. Plug the coordinates of the vertex (7, 1) in for x and y and solve for a.

y = a(x-6)(x-8)

What is the value of a?

• a = 1

• a = -1

• a = 7

• a = -7

What is the vertex of
f(x) = 2(x - 5)² + 12

• (-5, -12)

• (5,-12)

• (5, 12)

• (-5, 12)

To find the vertex from Factored Form: (reorder the steps)

• Solve & you have the y-value.

• Use the midpoint formula on the roots

• Solve & you have the x-value.

• Plug this value into the original equation.

To find the vertex from Factored Form: (reorder the steps)

• Use the midpoint formula on the roots

• Plug this value into the original equation.

• Solve & you have the y-value.

• Solve & you have the x-value.

When I want to find the maximum or minimum height of an object, I should_____

• Set the equation = 0 and solve.

• Use x = (-b/2a) as my answer.

• Substitute x = 0 into the equation.

• Find the y-coordinate for the vertex.

What is the maximum/minimum of a parabola called?

• vertex

• point

• top

• bottom