Ответ:
Пошаговое объяснение:
х + (7 - 2х) = 10
х + 7 - 2х = 10
-х = 10 - 7
-х = 3
х = - 3
проверка: - 3 + (7 - 2 * (- 3)) = - 3 + (7 + 6) = - 3 + 13 = 13 - 3 = 10
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3х + 5 = - 4х + 19
3х + 4х = 19 - 5
7х = 14
х = 14 : 7
х = 2
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х + 3 (1 - 2х) = 23
х + 3 - 6х = 23
-5х = 23 - 3
-5х = 20
х = 20 : (-5)
х = -4
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1/3х - 1 = 1/4 (х + 4/5)
1/3х - 1 = 1/4х + 1/5
1/3х - 1/4х = 1/5 + 1
4/12х - 3/12х = 1/5 + 5/5
1/12х = 6/5
х = 6/5 : 1/12
х = 6/5 * 12/1
х = 72/5
х = 14 2/5
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