6th Grade Math Textbook, Fundamentals

Lesson 2-2 for exercise sets. &KDSWHU 

3UDFWLFH   $FWLYLWLHV

Evaluate each expression when a3, b2, and c5.

1.abc 2.a^2 |c| 3.c^3  4 ab^2 4.b(a c)

Simplify each expression by combining like terms.

5. 3 m^2 n|8|  2 m^2 n 6. 4 ww 3 7. xy^2  5  3 xy^2  2 xy^2 |7|

8.Discuss and Write When evaluating an expression, is it easier to combine

terms first or to substitute values first? Justify your answer with examples.

An algebraic expression can have one or more. Terms are separated by

plus or minus signs. You can simplify an algebraic expression by combining

like terms. are those with the same variables raised to the same power.

Terms with no variables are also like terms. An expression is in

when it has no like terms.

3 xy  4  6 xy 2 x  5 xy  7 x^2

A term that does not contain a variable is called a.

The numerical factor of a term containing a variable is called a.

3 terms

simplest form

Like terms

terms

coefficient

constant

5 is the coefficient of 5x. 1 is the coefficient of x.

5 x 3  x 82 constants

It is sometimes necessary to use properties to simplify an expression.

like terms unlike terms

Simplify: 5x 2 y 3 x 8

5 x 3 x 2 y 8

8 x 2 y 8 Combine like terms (5x 3 x).

Use the Commutative

Property.

1

Simplify: 4n 3 n |–5| 2 n 6

4 n 3 n 2 n |–5| 6

9 n 11 Combine like terms

(4n 3 n 2 n) and (5 6).

Use the

Commutative

Property.

3 Simplify: 31 9 n^2 s 5  n^2 s

31  5  9 n^2 s n^2 s

31  5  (9 1)n^2 s

36  10 n^2 s Combine like terms

(31 5) and (9 1).

Use the Distributive

Property.

Use the Commutative

Property.

4

Simplify: 9(x y) 3 y

 9 x ( 9 y) 3 y

 9 x 9 y 3 y ( 9 y)  9 y

 9 x 12 y Combine like terms (9y 3 y).

Use the Distributive

Property.

2