April 19

Today:

Warm-Up: Review Solving Quadratic Options

New Topic: Quadratic Formula

Class Work

April 19, 2013

Warm-Up:

1. Solve by factoring: x2 + 6x - 7 = 0

x = - 7; x = - 1

1a. Now, find the axis of symmetry and vertex

2. Solve by Completing the square: ( )2 = ??

AOS = -3

Vertex = (-3, 16)

2a. What do you notice? 3. When graphing a quadratic, it may be easier/faster to complete the square even if the equation can be factored.

Warm-Up:

3. Graph the parabola f(x) = x2 - 6x + 8. Name the zeros, the vertex coordinates, and the axis of symmetry.4. Find the zeros, axis of symmetry and

vertex coordinates of the parabola y = -2x2 - 12x - 16 = 0

AOS = -3

Vertex = (-2, 2)

Zeros = -3

Warm-Up:

5. Use any method to find the roots, axis of symmetry, and vertex of y = -x2 + 4x - 46. Use any method to find the roots, axis of symmetry, and vertex of 2x2 - 20x + 50 = 07. Factor completely: y2 + 2x + yx + 2y 8. Complete the Square: 25x2 + 40x - 9 = 0

The Quadratic Formula:

x2 + 2x + 1 = 0 x = -1- 2 ± 0 2

The Quadratic Formula:

2. Solve: 2x2 + 5x + 3 = 0Is there an easier way to solve? Factoring?

Square Roots? Completing the square? The quadratic formula is likely the easiest and best method for solving.

x = -1, -1.5

3. Solve: 4x2 + x + 5 = 0

No Real Solution

The Quadratic Formula:

Conjugate: Joined together, especially in a pair. Connected.

x2 + 2x + 1 = 0

x = -1

- 2 ± 0 2

Class Work

Problems 1 - 9; show all work