Page 136 - Basic College Mathematics with Early Integers

Vocabulary and Readiness Check

Use the choices below to fill in each blank. Some choices may be used more than once.

evaluating the expression variable(s) expression
1. A combination of operations on letters (variables) and numbers is a(n) .
2. A letter that represents a number is a(n) .
3. 3x - 2y is called a(n) and the letters x and y are .
4. Replacing a variable in an expression by a number and then finding the value of the expression is called
.

2.1 Exercise Set FOR EXTRA HELP

Objective Complete the table.The first row has been done for you. See Examples 1 through 5.

a b a b a b a # b a b
45 9 54 36 405 5
1. 21 7
2. 24 6
3. 152 0
4. 298 0
5. 56 1
6. 82 1

Evaluate each expression for x = 2, y = 5, and z = 3. See Examples 1 through 5.

7. 3 + 2z 8. 7 + 3z 9. 6xz - 5x 10. 4yz + 2x

11. z - x + y 12. x + 5y - z 13. 3x - z 14. 2y + 5z

3
2
3
15. y - 4x 16. y - z 17. 2xy - 6 18. 3yz + 1
2
4
4
19. 8 - (y - x) 20. 5 + (2x - 1) 21. y + (z - x) 22. x - (y - z)

6xy 8yz 2y - 2 6 + 3x
23. 24. 25. 26.
z 15 x z

x + 2y 2z + 6 5x 10 70 15
27. 28. 29. - 30. -
z 3 y y 2y z

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