Is the problem (5/6)x - 1/8 = 7/8 or 5/(6x) - 1/8 = 7/8? As you wrote it, it's the second option. But I'll solve both.
(5/6)x - 1/8 = 7/8
(5/6)x = 1 [Added 1/8 to both sides]
x = 6/5 [Multiplied both sides by 6/5]
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5/(6x) - 1/8 = 7/8
5/(6x) = 1 [Added 1/8 to both sides]
5/6 = x [Multiplied both sides by x]
