Function notation: read and evaluate f(x), including f(x + 2) and f(2x)

Answer Key - Grade 9 Math Worksheet - Challenge Me

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

1. 1.

   Bo scores a game with the rule f(x) = 3x + 2. What is f(x + 4) with no parentheses and like terms combined?

   3x + 14
2. 2.

   Esme's pencil shop uses the rule f(x) = 2x − 5. What is f(x + 3) with no parentheses and like terms combined?

   2x + 1
3. 3.

   Jun's bell game uses the rule f(x) = 4x + 1. What is f(x − 2) with no parentheses and like terms combined?

   4x − 7
4. 4.

   Kira's drum game uses the rule f(x) = 5x − 3. What is f(x − 1) with no parentheses and like terms combined?

   5x − 8
5. 5.

   Luz has the rule f(x) = 2x + 5. What is f(3x) with no parentheses and like terms combined?

   6x + 5
6. 6.

   Noah has the rule f(x) = x² − 5. What is f(2x) with no parentheses and like terms combined?

   4x² − 5
7. 7.

   Pia has the rule f(x) = x² + 1. What is f(3x) with no parentheses and like terms combined?

   9x² + 1
8. 8.

   Tala's kite climbs by f(x) = cx + 6, and f(3) = 21. What is c?

   5
9. 9.

   Zee's sled run follows f(x) = cx + 4, and f(4) = 28. What is c?

   6
10. 10.

    Ari's tree grows by f(x) = cx + 8, and f(2) = 14. What is c?

    3