Unit 5 Lesson 9 Portfolio (Modified)
Show all work and/or include explanations to earn full credit (20 pts)
Quadratic Equations and Functions
1. Identify the vertex and the axis of symmetry of the parabola.
Answer:
2. Solve 4×2 = 28 by finding square roots.
Answer and work:
3. Find the x-intercepts of y = −3×2 + 4x + 4 using the Quadratic Formula.
Answer and explanation:
4. A biologist took a count of the number of migrating geese in a state park, and recounted the park’s population of geese on each of the next six weeks.
a. Find a quadratic function that models the data shown as a function of x, the number of weeks.
b. Use the model to estimate the number of geese at the lake on week 8.
Click the button next to the response that best answers the question.
• P(x)= 44×2 − 198x + 762; 1994 geese
• P(x)= 42×2 − 186x + 762; 1962 geese
• P(x)= 41×2 − 179x + 756; 1948 geese
• P(x)= 45×2 − 198x + 756; 2052 geese
Work:
5. Simplify 2i(5 − i).
Answer and work:
6. Find the first three output values of the fractal-generating function f(z) = z2 − 1 + 2i. Use z = 0 as the first input value.Click the button next to the response that best answers the question.
• −1 + 2i , −4 − 2i , 11 + 18i
• −1 + 2i , −4 − 2i , 19 − 14i
• −1 + 2i , −2 −+ 2i , −1 + 4i
• −1 + 2i , 2i , 3 + 2i
Work:
7. Factor x2 − 16.
Answer and work/explanation:
8. Factor x2 − 6x + 8.
Answer and work/explanation:
9. Solve 6×2 = 48. If necessary, round your answer to the nearest hundredth.
Answer and work/explanation:
10. Use the GCF to factor 15×2 + 6x.
Answer and work/explanation:
11. Solve 8×2 − 80x = −24 by using the Quadratic Formula.
Answer and work/explanation:
12. Identify points corresponding to P′ and Q′, the reflections of P and Q over the parabola’s axis of symmetry.
Answer:
13. Factor t2 − 10t + 25.
Answer and work/explanation:
14. Solve 3×2 + 2x + 1 = 0 by using the Quadratic Formula.
Answer and work/explanation:
15. Find the x-intercepts ofy= 2×2 + 4x + 2.
Answer and work/explanation:
16. Simplify using the imaginary number i.
Answer and work/explanation:
17. Graph y = −x2 − 1.Click the button next to the response that best answers the question.
•
•
•
•
18. Find a quadratic model for the values in the table.
Answer and work/explanation:
19. Find the quadratic function y = ax2 + c with a graph that includes (0, ) and (−3, ).Click the button next to the response that best answers the question.
• y = 3×2 +
• y = −3×2 +
• y = 3×2 −
• none of these
Answer and work/explanation:
20. The graph of y = −2×2 + 15x + c contains (3, 89). Find the value of c.
Answer and work/explanation: