1. Algebra I Unit 8 mid-unit Review

2. Unit 8 mid-unit Review
Given a quadratic function in vertex form: f(x) = -3(x + 5)2 – 4
Which of the following statements are true?
Adding 8 to the function shifts the graph up yes no
The graph of the function opens down yes no
The vertex is at the point (5, -4) yes no
Changing the 5 in the function makes the graph wider yes no

3. Answer Unit 8 mid-unit Review Pairs are: A & D, B & H, and F & G
Given a quadratic function in vertex form: f(x) = -3(x + 5)2 – 4
Which of the following statements are true?
Adding 8 to the function shifts the graph up yes no
The graph of the function opens down yes no
The vertex is at the point (5, -4) yes no
Changing the 5 in the function makes the graph wider yes no
Pairs are: A & D, B & H, and F & G

4. Unit 8 mid-unit Review
A diver jumps from a diving board that is 10 feet above the water. She reaches the peak of her dive seconds after leaving the diving board and she is feet above the water. She is still 16 feet above the water 1.5 seconds after the jump.
Write a function in vertex form to model the relationship between time from the beginning of the jump (x) and the height of the diver above the water (y).

5. Answer Unit 8 mid-unit Review
A diver jumps from a diving board that is 10 feet above the water. She reaches the peak of her dive seconds after leaving the diving board and she is feet above the water. She is still 16 feet above the water 1.5 seconds after the jump.
Write a function in vertex form to model the relationship between time from the beginning of the jump (x) and the height of the diver above the water (y).
Vertex at (0.875, 22.25)
y = a(x – 0.875)
Use point on parabola (1.5, 16)
16 = a(1.5 – 0.875)
a = -6.25
a = -16
So, y = -16(x – 0.875)

6. Unit 8 mid-unit Review Write the equation in vertex form.
y = -3x2 + 12x – 8

7. Answer Unit 8 mid-unit Review Write the equation in vertex form.
y = -3x2 + 12x – 8
Axis of symmetry:
x = -b/(2a) = -12/((2)(-3) = 2
y-coordinate of vertex:
y = -3(2)2 + 12(2) – 8 = 4
So vertex is at (2, 4)
Equation: y = -3(x – 2)2 + 4

8. Unit 8 mid-unit Review
Find the x-intercepts.
y = 4(x – 5) 2 – 36

9. Answer Unit 8 mid-unit Review Find the x-intercepts.
y = 4(x – 5) 2 – 36
x = 2 or 8
(2, 0) or (8, 0)

10. Unit 8 mid-unit Review
Solve this equation. Give exact answer (simplest radical form).
0 = -x2 + 10x + 2

11. Answer Unit 8 mid-unit Review
Solve this equation. Give exact answer (simplest radical form).
0 = -x2 + 10x + 2