6th Grade Math Textbook, Progress

Combine Like Terms

Before evaluating some algebraic expressions, you can simplify them

by combining like terms.

The parts of an algebraic expression that are separated by an

addition or subtraction sign are called terms. Terms that have

exactly the same variable parts are called like terms.

7 a
 10 a 19 x^2 
 15 x 4 x^2

1

2

like terms like terms

Simplify by combining like terms. Then evaluate the expression

for the given value of the variable.

12 w 5 w
30, when w1.5

(12w 5 w)
 30 Associative Property

(125)w
 30 Distributive Property

7 w
 30 Simplify.

7 • 1.5
 30 Replace wwith 1.5.

40.5

8 c^2  6 c
 3 c^2 , when c 4

8 c^2 
 3 c^2  6 c Commutative Property

(8
3)c^2  6 c Distributive Property

11 c^2  6 c Simplify.

11 • 42  6 • 4 Replace cwith 4.

value of the expression 152 value of the expression

Simplify by combining like terms. Then evaluate the

expression for the given value of the variable.

5. 20 n 6 n3, when n2.5 6. 6 x
   7 x
   14, when x0.34


6. 378
   15 y 2 y, when y3.1 8. 7 m^2
   3 m^2
   2, when m 3


7. 9 z^2  5 z
   3 z^2 , when z 10 10. 13 b
   6 b 19
   14 c, when b 15
   and c0.4

Write and evaluate an algebraic expression.

11. Juan buys some T-shirts for $12.95 12.Lucy orders books from an online
    each and pays a sales tax of $2.33. bookstore. She pays $12 per book and
    If he buys 3 T-shirts, how much does $8.95 for shipping and handling. How
    Juan pay in all? much does she pay in all for 13 books?


12. Stanley packs some paperback books in each of 5 boxes and
    some hardcover books in each of 4 boxes. If he packs 15 paperback
    books in each box and 11 hardcover books in each box, how many
    books in all does he pack?

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