А) 4х + 1 = - 3х + 15
4х + 3х = 15 - 1
7х = 14
х = 2
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б) 4х + 2(1 - 3х) = 13
4х + 2 - 6х = 13
- 2х = 13 - 2
2х = - 11
х = - 5,5
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в) 1/2х - 1 = 1/3(х + 3/4)
1/2х - 1 = 1/3х + 1/4
1/2х - 1/3х = 1 + 1/4
3х - 2х = 1 1/4
х = 1 1/4