а) (х+240)*3=1260
3х+720=1260
3х=1260-720
3х=540
х=540:3
х=180
(180+240)*3=1260
б) х+(240*3)=1260
х+720=1260
х=1260-720
х=540
540+(240*3)=1260
(х+240)*3=1260
х=1260 :3
х=420
х=420-240
а) (х+240)*3=1260
3х+720=1260
3х=1260-720
3х=540
х=540:3
х=180
(180+240)*3=1260
б) х+(240*3)=1260
х+720=1260
х=1260-720
х=540
540+(240*3)=1260
(х+240)*3=1260
х=1260 :3
х=420
х=420-240
х=180
(180+240)*3=1260