Ответ:

Пошаговое объяснение:

1)х-7ц.1/3=12ц.5/12

x = 12ц.5/12 + 7ц.1/3

x = 12ц.5/12 + 7ц.4/12

x = 19ц.9/12

x = 19ц.3/4

2)(5ц.7/9-х)+2ц.3/4 =3ц.5/12

5ц.7/9 - x + 2ц.3/4 = 3ц.5/12

5ц.28/36 - x + 2ц.27/36 = 3ц.15/36

7ц.55/36 - x = 3ц.15/36

x = 7ц.55/36 - 3ц.15/36

x = 4ц.40/36

x = 5ц.4/36

x = 5ц.1/9