Ответ:2*x-267 =133

2*x=133+267=400

X=400:2=200

300-78:x=287

78:x=300-287=13

X=78:13=6

287+(120-x)=300

120-X=300-287=13

X=120-13

X=107

750+10*x=750

10*x=750-750=0

X=0