What is the shape of this graph?
The shape is a parabola.
What is the formula for vertex form? Hint: f(x) = ???
f(x) = a(x - h)2 + k
What is the formula for a standard form quadratic function. f(x) = ???
f(x) = ax2 + bx + c
Calculate the residuals for the actual and predicted y in the chart.
Is this quadratic function a good fit for the data?
Yes, the function is a good fit because there are positive and negative residuals.
If you find that the 2nd differences of y-values for a function are the same, then the function can be modeled with a _________ function.
quadratic
What is the point in the center of the parabola called? It is shown here in black.
The point is the vertex.
Identify a, h, and k in the function f(x) = 3(x - 2)2 + 4
a = 3
h = 2
k = 4
Find the axis of symmetry and y-intercept for the function f(x) = x2 + 8x - 7
y-intercept: (0, -7)
Write a quadratic function in standard form to model the area of the painting. Hint: Multiply the height by the width.
f(x) = 2x2 + 13x + 20
What type of function can be used to model this data? Why?
A linear function because the first differences are the same.
What is the line down the center of the parabola called? It is shown here as x = 3.
The line down the center of the parabola is the axis of symmetry.
What are the vertex and axis of symmetry of the function f(x) = 0.5(x + 4)2 + 7
vertex = (-4, 7)
axis of symmetry, x = -4
Change the function f(x) = -2(x - 3)2 - 5 into standard form.
What is the y-intercept?
f(x) = -2x2 + 12x - 23
y-intercept: (0, -23)
Write a vertical motion model in the form h(t) = -16t2 + v0t + h0 for the situation below:
Teddy kicks a soccer ball with an initial velocity of 32 f/s and an initial height of 0 ft
h(t) = -16t2 + 32t
What type of function best models the data shown? Why?
An exponential function because the ratios of y-values are the same
What is the point called where the parabola crosses the y-axis? Hint: It is shown here at (0, 5).
The point is the y-intercept.
What is the function in vertex form for the parabola shown?
f(x) = 2(x - 3)2 - 4
What is the function for this graph in standard form?
f(x) = -x2 - 6x - 10
Marco has a 12 ft by 12 ft patio. He wants to enlarge it by x feet on three sides as shown. Write a function in standard form to model the size of the patio in square feet.
f(x) = 2x2 + 36x + 144
Which type of function best models the data shown? Why?
Quadratic function, because the second differences are the same.
What are the points where the parabola crosses the x-axis called? There may be none, one, or two of these points. They are shown here at (-3, 0) and (4, 0)
The points are the roots.
Graph the function f(x) = -0.5(x + 2)2 + 1 and identify the axis of symmetry.
Axis of Symmetry: x = -2
Graph the function f(x) = -x2 + 10x + 20
What is the vertex?
Vertex: (5, 5)
Write a function using h(t) = -16t2 + v0t + h0 to model the vertical motion of an object with an initial vertical velocity of 48 ft/s and initial height of 10 feet.
Will the object hit the ceiling in a stadium that is 50 feet high?
h(t) = -16t2 + 48t + 10
No, the object's maximum height is only 46 feet.
Which type of function best models the data shown? Write a function to fit the data.
A linear function is the best fit.
The function that models the data is f(x) = 7x - 9