1. Day 15: Quadratics

2. 1. Which ordered pair represents one of the roots of the function f(x) = 2x 2 + 3x − 20? F (− 5/2, 0) H (−5, 0) G(−4, 0) J (−20, 0)

3. 2. The graph of y = x 2 + 2x − 8 is shown below. Which coordinate pair best represents the vertex of this graph? F (−4, 0) G (2, 0) H (0, −8) J (−1, −9)

4. 3. What is the x intercept of 3x + 12y = 21?

5. 4. The completion of a certain chemical reaction is expressed by the equation y = 250 − 5x − x 2, where y is the number of seconds needed to complete the reaction and x is the temperature in degrees Celsius at which the reaction occurs. If the reaction is complete in 200 seconds, what is the temperature at which the reaction occurs? A 5°C B 7°C C 10°C D 12°C

6. 5. What is the parent function of y = 7x – 18?

7. 6. What are the zeros of the function y = 1/2 (x + 4)(x − 6)? A −4 and 6 C 4 and −6 B −3 and 2 D −2 and 3

8. 7. What is the solution set for the equation 2x 2 − 16x − 96 = 0? A {4, 12} C {−4, −12} B {−4, 12} D {4, −12}

9. 8. What is the slope of 15y + 5x = 120? Hint: If you get -3 you are wrong!

10. 9.

11. 10. Simplify (2x + 1) (3x – 4)

12. 11. The graph below shows the height of a baseball from the time it is thrown from the top of a building to the time it hits the ground. How much time elapses while the baseball is 80 meters or more above the ground? F 1 sec G 9 sec H 7 sec J6 sec

13. 12. Which of the below simplifies 3( x + 2) - 3( 2x – 1)? a. -3x + 3 b. -3x + 9 c. 3x 2 + 6x – 12 d. 3x 2 – 3x + 12

14. 13. Which of the following polynomial equations best represents this graph? A (x + 6)(x − 2) = y B (x − 2)(x − 16) = y C (x − 6)(x + 2) = y D (x + 2)(x + 16) = y