Помогите проверить 2/3x-2/6x-1=1/1/4

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2/3х - 2/6х -1 = 1 / 1/42/3х - 1/3х- 1 = 41/3х = 4+11/3х = 5Х= 5:1/3Х= 5*3:1Х= 15--------2/3*15 - 2/6*15 - 1 = 1 / 1/410 - 5 -1 = 44= 4