Points on a Graph
What does "a" equal?
2x² - 7x + 8 = 0
a = 2
What is this form called?
y = ax2+bx+c
Standard Form.
In vertex form, (y=a(x-h)2+k), what does "a" represent?
Is this parabola being reflected over the x-axis?
y = 2(x - 1)² + 3
No, "a" is not negative.
What is the y-intercept of this parabola?
y = 2x2+4+6
(0, 6)
What is an advantage of using vertex form?
Quickly identifies vertex of the parabola. (h, k)
Label "a", "h", and "k"
y= 2(x-4)2-3
h = 4
k = -3
How many units is this parabola shifting on the x-axis, and in what direction?
y = -3(x + 2)² - 1
2 units to the left.
What is the vertex of this parabola?
y = 2(x - 3)2 + 1
(3, 1)
What is this form called?
y = a(x-h)2+k
Vertex Form.
In vertex form, (y = a(x - h)2 + k), what does "h" represent?
"h" represents the left or right shift of a function.
Is this a vertical stretch or compression?
y = 1/2x2
This is a compression. a < 1.
What does "c" equal?
y = 2x2+12x+18-22
c = -4
What is an advantage of using standard form?
Quickly identifies y-intercept. (c)
Label "a", "h", and "k"
y = -(x-4)2-3
h = 4
k = -3
How many units is this function shifting on the y-axis, and in what direction?
y = -2(x+3)2+4The graph shifts 4 units up.
What is the vertex of this parabola?
y = -2(x + 3)² + 5
(-3, 5)
What is this quadratic form called?
y = a(x-p)(y-q)
Factored Form.
In vertex form, (y = a(x - h)2 + k), what does "k" represent?
"k" represents the up or down shift of a function.
Is this a vertical stretch or compression?
y = 5/2x2
This is a vertical stretch. a > 1