1/14х-2/7*1 1/4=5/56
1/14х-2/7*5/4=5/56
1/14х-5/14=5/56
1/14х=5/56+5/14
1/14х=5/56+20/56
1/14х=25/56
х=25/56:1/14
х=25/56*14/1
х=6 1/4
7 1/4у-у=9 3/8
29/4у-4/4у=9 3/8
25/4у=9 3/8
у=9 3/8:25/4
у=75/8*4/25
у=3/2
у=1 1/2
7х-0,2х=30,6
6,8х=30,6
х=30,6:6,8
х=4,5