1. Objective- To find the opposite of a sum or difference.
- ( a + b ) =
- a + - b or
- a - b
- ( a - b ) =
- a + b

2. Simplify. 1) - ( 2x + 5 ) 2) - ( 4a - 7) - 2x - 5 - 4a + 7
3) a (a - 3) - ( 3a - a - 2) 2 2
a - 3a - 3a + a + 2 2
-2a - 2a + 2
4) 4 (x + 5) - (x - 2) - 3 ( x + 1)
4x x x - 3 19

3. Solve. 13 x - 3( 2 + 4x) = 25 13x - 6 - 12x = 25 + 6 +6 x = 31
x = 31

4. Solve. 3( x + 2 ) - ( 5x - 4 ) = - 1 3x + 6 - 5x + 4 = - 1 - 10 -10
-2x = -11
x = =

5. Very important when subtracting fractions.
Most Missed Problem! 4x
2x + 1 - 5 10 8x
2x + 1 - 10 10
8x - ( 2x + 1 ) 10
8x - 2x - 1
6x - 1 = 10 10

6. Simplify. - - = 3y 6y - 2 4 3 9y 4 (6y - 2) 12 12 9y - 4 ( 6y -2 ) 12

7. Simplify. - - = x - y - 5(x + 2y) 8 6 -20(x + 2y) 3 (x - y) 24 24