1. Solving Equations by Combining Like Terms
3x +12 – 4x = 20
Look: There are 2 variable terms …
… so, COMBINE LIKE TERMS first.
Remember,
‒1x = ‒x
but, just leave the 1 there.
–1x = 20
– – 12
Look at the variable side, find the constant,
and get rid of it first.
–1x = 8
2. To get rid of +12, add the opposite (‒12) –1 –1
3. Cancel the opposites …
… bring down the variable term
…then add.
4. To get rid of the coefficient, ‒1 … …
x = –8
… DIVIDE both sides by ‒1

2. Solving Equations by Combining Like Terms
Solve the equation. 3.
–8r – 2 + 7r = – 9
–6 = 11w –5w 1. 2.
4p p = 25
w = – 1
p = 3
r = 7

3. Solving Equations by using Distributive Property
EXAMPLE 3
6n –2(n +1) = 26
Use Distributive property
“outer times first”, then
6n –2(n +1) = 26
“outer times second”,
Combine like terms. 6n
–2n –2
= 26
4n – 2 = 26
+ 2
+ 2
Add 2 to each side.
4n = 28
Solve.
n = 7

4. Solving Equations by using Distributive Property1. 2. 3.
3(x – 9) = – 39
–63 = –7(8 – p)
25 = –3(2x + 1)
x = or – 4
x = – 4
p = –1