Lesson 2: Graphing f (x) = ax² + c — Practice Questions

1. 1. Find the positive zero of the function $f(x) = x^2 - 25$. The positive zero is ___.

2. 2. How many real zeros does the function $f(x) = 3x^2 + 12$ have?

   • A. Two real zeros
   • B. One real zero
   • C. No real zeros
   • D. Infinitely many zeros

3. 3. The function $g(x) = -4x^2 + 100$ has two zeros. What is the value of the positive zero? The answer is ___.

4. 4. What are the $x$-intercepts of the graph of the function $h(x) = x^2 - 49$?

   • A. (0, 7) and (0, -7)
   • B. (7, 0) and (-7, 0)
   • C. (49, 0) and (-49, 0)
   • D. The graph has no x-intercepts

5. 5. Find the negative zero of the quadratic function $f(x) = 50 - 2x^2$. The negative zero is ___.

6. 6. An apple is dropped straight down from a 40-foot tree. Which statement best describes the graph of the apple's height versus time?

   • A. It is a straight vertical line.
   • B. It is a parabola opening upward.
   • C. It is a straight diagonal line.
   • D. It is a parabola opening downward.

7. 7. A rock is dropped from a cliff. A second rock is thrown horizontally from the same cliff at the same time. How do the shapes of their height-time graphs compare?

   • A. The dropped rock's graph is a line; the thrown rock's is a parabola.
   • B. Both graphs are identical parabolas opening downward.
   • C. The graphs are different types of parabolas.
   • D. The dropped rock's graph is a parabola; the thrown rock's is a line.

8. 8. The height of a phone dropped from a balcony is modeled by the function $h(t) = -16t^2 + 81$. Based on this function, the phone was dropped from an initial height of ___ feet.

9. 9. True or False: The parabolic shape of a falling object's height-time graph is a direct picture of the object's curved path through the air.

   • A. True
   • B. False