1. a + 6 < 9 2.2n + 1 > 1 3.6- × < 4 4.3x + 1 > 13

1)
a + 6 < 9
a < 9 - 6
a < 3

2)
2n + 1 > 1
2n > 1 - 1
2n > 0
n > 0/2
n > 0

3)
6 - x < 4
- x < 4 - 6
- x < - 2
x > - 2/- 1
x > 2


4)
3x + 1 > 13
3x > 13 - 1
3x > 12
x > 12/3
x > 4

1. a + 6 < 9
= a < 9 -6
= a < 3

2. 2n + 1 > 1
= 2n > 1 -1
= 2n > 0
= n > 0/2
= n > 0

3. 6 -x < 4
= -x < 4 -6
= -x < -2
= x > 2

4. 3x + 1 > 13
= 3x > 13 -1
= 3x > 12
= x > 12/3
= x > 4

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