Vocabulary
The name of the graph of a quadratic function.
Parabola
The standard form of a quadratic function.
y=ax2+bx+c
What is the vertex?
y=3(x-5)2+8
(5 , 8)
Factor x2 + 7x + 6
(x + 6)(x + 1)
What is this form of a quadratic equation called?
y=ax2+bx+c
Standard Form
What is the formula for the x-coordinate of the vertex?
x=-b/(2a)
What is the vertex?
y=-1(x-4)2-7
(4 , -7 )
How do you know if a parabola opens downward?
If "a" is less than zero.
The lowest or highest point on the parabola.
Vertex
Which letter tells you about the stretch of a parabola?
a
Create an equation in vertex form:
a=2 Vertex = (5 , -4)
y=2(x-5)2-4
How do you know if a parabola opens upward?
If "a" is greater than 0.
Points where a parabola crosses the x-axis.
X intercepts (also called the "zeros" of the parabola)
What is the x-coordinate of the vertex?
y=2x2+12x-7
x = -3
Give an equation in vertex form.
This parabola is upside down with a vertex at (-2, 5)
y=-(x+2)2+5
When studying gravity, what is the acceleration on Earth?
9.8 m/s2
What is this form of a quadratic equation called?
y=a(x-h)2+k
Vertex Form
Find the vertex of this parabola.
y=x2-6x+8
Vertex (3 , -1 )
The vertex of the parabola is (-1, -1) and a = 1. Give the vertex form.
y=(x+1)2-1?
What is the vertex of this parabola?
y=3x2+5
(0,5)