Уравнения a)x+0,5x=3 б) x-1/3x=12 в) x+3/4x=28 . где 1/3 и 3/4 это дроби . как найти х?

Х + 0,5х = 3            х - 1/3х = 12            х + 3/4х = 28
1х + 0,5х = 3         1х - 1/3х = 12           1х + 3/4х = 28
1,5х = 3                 3/3х - 1/3х = 12        1 целая 3/4х=28
х = 3 : 1,5              2/3х = 12                  7/4 х = 28
х = 2                     х = 12 : 2/3               х = 28 : 7/4
                             х= 12 * 3/2               х = 28 * 4/7
                             х = 18                      х = 16