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3 x /4 = 5
⇔ 3 x = 20
⇔ x = 20/3
4 x - 3 = 11
⇔ 4 x = 11 + 3
⇔ 4 x = 14
⇔ x = 14/4 = 7/2
7 - 8 x = 56
⇔ - 8 x = 56 - 7
⇔ - 8 x = 49
⇔ x = - 49/8
6 x - 4 = 3 x + 14
⇔ 6 x - 3 x = 14 + 4
⇔ 3 x = 18
⇔ x = 6
9 - 2 x = 11 + 4 x
- 2 x - 4 x = 11 - 9
- 6 x = 2
x = - 2 /6 = - 1/3
5 (x - 3 ) - 3 x + 7
⇔ 5 x - 15 - 3 x + 7
⇔ 2 x - 8
5 x - 15 - 15 x + 35 = 9
⇔ 5 x - 15 x = 9 + 15 - 35
⇔ - 10 x = - 11
⇔ x = 11/10 = 1.1