Warm-up Factor these 4 problems in your notes

Birthdays 2nd Period Safiya Muqueet November 10th Austin Victor November 10th

Birthdays 3rd Period Lauren Miller November 9th Teresa Monreal November 12th

Quick Write Take out a single sheet of paper and write your name at the top. In the next 2 minutes, write down everything you know about Quadratics??

Substitute Tomorrow Please make sure she is welcomed! You will be using calculators to find key quadratic information

Section 4-2 Vertex Format Pages 245-251 Chapter 4 Section 4-2 Vertex Format Pages 245-251

Objectives I can read key information from vertex format: vertex point, AOS, and opening direction, plus find the y-intercept I can graph quadratic functions in vertex form.

is called a quadratic function. f (x) = a(x – h)2 + k is called a quadratic function. The graph of a quadratic function is a parabola. Every parabola is symmetrical about a line called the axis of symmetry (AOS). x y The intersection point of the parabola and the axis is called the vertex point of the parabola. f (x) = a(x – h)2 + k vertex Axis of Symmetry Quadratic function

Standard Vertex Format Standard Vertex Format of a quadratic y = a(x – h)2 + k Vertex is (h , k) Axis of Symmetry is x = h If a > o, then the parabola opens upward If a < o, then the parabola opens downward

Examples Vertex Format Vertex Axis of Sym y = (x – 0)2 + 0 (0,0) x = 0

y-intercept To find the y-intercept of any equation, let all the x’s be ZERO y = 3x2 + 6x + 9 y-intercept is (0, 9) y = 3(x – 2)2 - 4 y-intercept is (0, 8)

Ex 1: y = (x – 2)2 + 3 Vertex Point: AOS: Opening: y-int:

Ex 2: y = (x + 4)2 - 1 Vertex Point: AOS: Opening: y-int:

Ex 3: y =-2 (x + 1)2 - 5 Vertex Point: AOS: Opening: y-int:

Comparing How does Vertex Format compare with anything else you learned earlier this year? Transformations???

Homework Worksheet 5-5