Practice: Expressions & Equations

Part A: Write Algebraic Expressions

Directions: Write an algebraic expression for each phrase. Use x for the unknown number.

1. 6 more than a number

2. A number times 9

3. 4 less than a number

4. A number divided by 6

5. Twice a number plus 3

6. 10 minus a number

Directions: Evaluate each expression for the given value of the variable.

7. 4x + 3 when x = 5

8. 7y - 2 when y = 4

9. n/3 + 8 when n = 12

10. 2(x + 5) when x = 7

Directions: Solve each equation. Show your work and check your answer.

11. x + 8 = 15

x =

12. y - 6 = 11

y =

13. 7m = 42

m =

14. n/4 = 9

n =

15. x + 15 = 27

x =

16. 9p = 63

p =

Directions: Write an equation and solve.

17. Sarah has some stickers. After getting 12 more, she has 35 stickers. How many did she start with?

Equation:

Sarah started with stickers.

18. Marcus divided his baseball cards equally among 6 friends. Each friend got 8 cards. How many cards did Marcus have?

Equation:

Marcus had baseball cards.

19. A number multiplied by 5 equals 45. What is the number?

Equation:

The number is .

20. The cost of a book is $7 less than the cost of a game. If the book costs $18, how much does the game cost?

Equation:

The game costs $.

21. Write a word problem that could be solved with the equation 3x = 24. Then solve it.

22. If 2x + 5 = 17, what is the value of 3x?

Answer: 3x =

(Hint: First find x, then multiply by 3)