y = a b cx x2

x b2a

y = a b cx x2

2y 2 1x x

x b2a

x b2a

2y 6 5x x

x b2a

2y 2 8 1x x

x b2a

2y 8 2x x

1.Find the vertex point, (h, k):

2.a will be the a from the standard form equation.

3. Substitute into y = a (x-h)2 + k

( , ( ))2 2

b bf

a a

1.Convert y = 2x2 – 4x + 5

2.Convert y = -x2 – 2x + 1

Vertex = (1, 3)

Vertex form: y = 2(x-1)2 + 3

Vertex = (-1, 2)

Vertex form: y = -(x+1)2 + 2

3. y = 8x2 – 64x - 3

Vertex = (4, -131)

Vertex form: y = 8(x-4)2 - 131

Philip’s tossing of the rock can be represented by the equation:

h(t) = -16t2 + 48t + 64

Using your knowledge of how to find the vertex from today’s lesson now answer the following questions.

a. Identify the vertex and the axis of symmetry of the graph.

b. What is the maximum height the rock reaches above the surface of the lake?

c. After how many seconds does the rock hit the surface of the lake?