Parabola Formulas Summary of Day One Findings Horizonal

Parabola Formulas Summary of Day One Findings Horizonal Parabolas Vertical Parabolas (Type 2: Right and Left) (Type 1: Up and Down) Vertex Form Vertex: (h, k) Axis: x = h Vertex Form Vertex: (h, k) Axis: y = k Opens: a (+ up; – down) Opens: a (+ right; –left)

Find VERTEX FORM EQUATION: Given Vertex & Point Plug vertex into appropriate vertex form equation and use another point to solve for “a”. [A] Opening Vertical [B] Opening: Horizontal Vertex: (2, 4) Vertex: (- 4, 6) Point: (-6, 8) Point: (2, 8)

COMPLETING THE SQUARE REVIEW Find the value to add to the trinomial to create a perfect square trinomial: (Half of “b”)2 [A] [B] [C] [D]

STANDARD FORM to VERTEX FORM Method #1: COMPLETING THE SQUARE • Find the value to make a perfect square trinomial to the quadratic equation. (Be careful of coefficient for x 2 which needs to be distributed out) • ADD ZERO by adding and subtracting the value to make a perfect square trinomial so as to not change the overall equation (Be careful of coefficient for x 2 needs multiply by subtraction)

Example 1 Type 1: Up or Down Parabolas Write in vertex form. Identify the vertex and axis of symmetry. [A] [B]

Example 2 Type 2: Right or Left Parabolas Write in vertex form. Identify the vertex and axis of symmetry. [A] [B]

Example 3 Type 1: Up or Down Parabolas Write in standard form. Identify the vertex and axis of symmetry. [A] [B]

Example 4 Type 2: Right or Left Parabolas Write in vertex form. Identify the vertex and axis of symmetry. [A] [B]

Method #2: SHORTCUT 1. Find the AXIS of SYMMETRY : Axis equation opposite Quadratic 2. Find VERTEX (h, k) of STANDARD FORM 3. “a” – value for vertex form should be the same coefficient of x 2 in standard form. Check by using another point (intercept) PRACTICE METHOD #2: [1] Write in vertex form. Find vertex and axis of symmetry. [2]