4x-7=8x-2
4x - 8x = - 2 + 7
- 4x = 5 .(-1)
4x = -5
x = -5/4
x = - 1,25
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2x+1=4x-7
2x - 4x = -7 -1
- 2x = - 8 . (-1)
2x = 8
x = 8/2 = 4
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9x+9+3x=15
9x + 3x = 15 - 9
12x = 6
x = 6/12
x = 0,5
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16x-1=12x+3
16x - 12x = 3 + 1
4x = 4
x = 4/4
x = 1
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3x-2=4x+9
3x - 4x = 9 + 2
- x = 11 .(-1)
x = - 11