(х - 1 3/4) * 2/3 = 0 можно еще так покороче
2/3 * х - 2/3 * 1 3/4 = 0 (х - 1 3/4) * 2/3 = 0
2/3х - 2/3 * 7/4 = 0 х - 1 3/4 = 0 : 2/3
2/3х - 1/3 * 7/2 = 0 х - 1 3/4 = 0
2/3х - 7/6 = 0 х = 0 + 1 3/4
2/3х = 0 + 7/6 х = 1 3/4
2/3х = 7/6
х = 7/6 : 2/3
х = 7/6 * 3/2
х = 7/2 * 1/2
х = 7/4
х = 1 3/4
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12(х - 1 3/10 * 5/6) = 0
х - 1 3/10 * 5/6 = 0 : 12
х - 13/10 * 5/6 = 0
х - 13/2 * 1/6 = 0
х - 13/12 = 0
х = 0 + 13/12
х = 13/12
х = 1 1/12