Linear, quadratic or exponential? And which grows faster in the end?

Answer Key - Grade 9 Math Worksheet

Circle the best answer, or write your answer on the line.

1. Read this first

   Growth table

   x	y
   0	400
   1	200
   2	100
   3	50
   4	25

2. 1.

   Zee pours half of a jug of water into a plant pot, again and again. The table shows the mL left in the jug. Is the table linear, quadratic or exponential?

   • Quadratic: the gaps change by the same amount
   • Exponential: equal factors
   • Linear: equal gaps
3. 2.

   Ari counts blocks in a growing block pattern. Is the table linear, quadratic or exponential?

   • Linear: equal gaps
   • Quadratic: the gaps change by the same amount
   • Exponential: equal factors
4. 3.

   Bo counts cells in a science-video table. Is the table linear, quadratic or exponential?

   • Linear: equal gaps
   • Quadratic: the gaps change by the same amount
   • Exponential: equal factors
5. 4.

   Kira plots a rocket game's points. Is the graph linear, quadratic or exponential?

   • Linear: equal gaps
   • Quadratic: the gaps change by the same amount
   • Exponential: equal factors
6. 5.

   Noah plots pencils in a growing box display. Is the graph linear, quadratic or exponential?

   • Quadratic: the gaps change by the same amount
   • Exponential: equal factors
   • Linear: equal gaps
7. 6.

   Ren's timer rules: A is y = 4x + 8, B is y = 2^x. Checking x = 0, 1, 2 and up, what is the first x where B is bigger?

   5
8. 7.

   Ari's star-chart rules: A is y = 15x + 21, B is y = 3^x. Checking x = 0, 1, 2 and up, what is the first x where B is bigger?

   5
9. 8.

   Bo's club tries two reading plans. On day 0, Plan A has 100 points and Plan B has 1. A adds 20 a day; B doubles each day. Which has more on day 30?

   • Plan B
   • Plans A and B tie
   • Plan A
10. 9.

    Esme compares Rule A, y = 50x², and Rule B, y = 2^x. At x = 10, A is 5,000 and B is 1,024. Which rule is bigger at x = 20?

    • Rule B
    • Rule A
    • Rules A and B tie
11. 10.

    Jun compares two games. At level 0, Game A gives 500 coins and Game B gives 2. A adds 100 a level; B doubles each level. Which gives more at level 15?

    • Games A and B tie
    • Game B
    • Game A