1. EXAMPLE 3 Combining Like Terms a. 3x + 4x = (3 + 4)x = 7x b.
Distributive property
= 7x
Add inside grouping symbols. b.
–9y + 7y + 5z
= (–9 + 7)y + 5z
Distributive property
= –2y + 5z
Add inside grouping symbols.

2. Simplifying an Expression
EXAMPLE 4
Simplifying an Expression a.
2(4 + x) + x
= 8 + 2x + x
Distributive property
= 8 + 3x
Combine like terms. b.
–5(3x – 6) + 7x
= –15x x
Distributive property
= –8x + 30
Combine like terms.

3. Simplify the expression by combining like terms.
GUIDED PRACTICE
for Examples 3 and 4
Simplify the expression by combining like terms. 7.
2(x + 4) + 3x – 5
2(x + 4) + 3x – 5
= 2x x – 5
Distributive property
= 5x + 8
+ (–5)
Add.
= 5x + 3
Combine like terms.

4. Simplify the expression by combining like terms.
GUIDED PRACTICE
for Examples 3 and 4
Simplify the expression by combining like terms. 8.
5y + 9z – 7 – 3y
5y + 9z – 7 – 3y
= (5 – 3)y
+ 9z – 7
Distributive property
= 2y + 9z – 7
Combine like terms.

5. Simplify the expression by combining like terms.
GUIDED PRACTICE
for Examples 3 and 4
Simplify the expression by combining like terms. 9.
–3(6x + 2y) + 22x
–3(6x + 2y) + 22x
= –18x – 6y + 22x
Distributive property
= 4x – 6y
Combine like terms.