№ 369
(х + 9)/3 - х/5 = 1
5(х + 9) - 3х = 15
5х + 45 - 3х = 15
2х = - 45 + 15
2х = - 30
х = - 15
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№370
(х-6)/4 - х /3 = 1
3(х - 6) - 4х = 12
3х - 18 - 4х = 12
- х = 12 + 18
х = - 30
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4х - 5,5 = 5х - 6х + 4,5
4х - 5х + 6х = 5,5 + 4,5
5х = 10
х = 2
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4 - 15х + 12,5 = 3х + 9,5
-15х - 3х = 9,5 - 12,5 - 4
- 18х = -7
х = 7/18
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10 + 7,5х - 0,5х = 24
7х = 24 - 10
7х = 14
х = 2
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1,5х -12 + 8,5х = 18
10х = 18 + 12
10х = 30
х = 3
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