X+3=11 x+7=19 x-8=5 x-9=4 60-x=59 12-x=12
X+3=11 x+7=19 x-8=5 x-9=4 60-x=59 x=11-3 x=19-7 x=5+8 x=4+9 -x=-60=59 x=8 x=12 x=13 x=13 -x=-1 |:-1 x=1
1) X - 3 = 11 X = 11+3 X=14 Проверка: 14-3=11 11=11 2)X+7=19 X=19-7 X=12 Проверка : 12+7=19 19=19