2x = 30
divide both sides by 2
x = 30/2
x = 15

5x - 1 = 3x
add 1 to both sides
5x = 3x + 1
subtract 3x from both sides
5x - 3x = 1
2x = 1
divide both sides by 2
x = 1/2

3.53x + 1 = 65.4
subtract 1 from both sides
3.53x = 65.4 - 1
3.53x = 64.4
divide both sides by 3.53
x = 64.4/3.53
x = 18.24

16x - 4 = 33 - x
add 4 to both sides
16x = 33 - x + 4
16x = 37 - x
add x to both sides
17x = 37
divide both sides by 17
x = 37/17
x = 2.18

7x - 2 = 5x
add 2 to both sides
7x = 5x + 2
subtract 5x from both sides
2x = 2
divide both sides by 2
x = 1

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