1,2-(х-1/4)=1/2 СОРОЧНО УМОЛЯЮ!!!!
1,2-(х-1/4)=1/2
1 2/10 -(х-1/4)=1/2
х-1/4=1 2/10-1/2
х-1/4=12/10-1/2
х-1/4=12/10-5/10
х-1/4=7/10
х=7/10+1/4
х=14/20+5/20
х=19/20