1. Equations With Variables on Both Sides
Algegra 1: Section 2-4
Equations With Variables on Both Sides

2. Objectives: To solve equations with variables on both sides
To identify equations that are identities or have no solution

3. Variables on Both sides
7k – 4 = 5k + 16
7k = 5k + 20
-5k k
2k = 20
k = 10
2(c – 6) = 9c + 2
2c – 12 = 9c + 2
2c = 9c + 14
-9c c
-7c = 14
c = -2

4. Identity
An equation whose answer is ALWAYS true is called an IDENTITY.
EXAMPLE:
9 + 5x = 7x + 9 – 2x
5x = 7x – 2x
5x = 5x
The answer is an identity because 5x always = 5x.

5. Equations with no solutions:
An equation whose solution is NEVER true has NO SOLUTION.
9 + 5n = 5n – 1
10 + 5n = 5n
- 5n - 5n
10 = 0
The solution is NEVER true, so the answer is No Sol.

6. Check understanding:
4p – 10 = p+3p – 2p
18x – 5 = 3(6x – 2)

7. Assignment:
Pg. 98: multiples of 3 #3-39, 46, 55, 56, 63