1) 25 + (x-2)*15 = 7025 + 15x - 30 = 7015x - 5 = 7015x = 75x = 5
2) 72:(12-x:4) = 972 / (12 - x/4) = 98 = 12 - x/4x/4 = 4x = 16
Проверка:
1) 25 + (5-2)15 = 7025 + 315 = 7025 + 45 = 7070 = 70
2) 72:(12-16:4) = 972 / (12 - 4) = 972 / 8 = 99 = 9
Уравнения верно решены и проверены.
1) 25 + (x-2)*15 = 70
25 + 15x - 30 = 70
15x - 5 = 70
15x = 75
x = 5
2) 72:(12-x:4) = 9
72 / (12 - x/4) = 9
8 = 12 - x/4
x/4 = 4
x = 16
Проверка:
1) 25 + (5-2)15 = 70
25 + 315 = 70
25 + 45 = 70
70 = 70
2) 72:(12-16:4) = 9
72 / (12 - 4) = 9
72 / 8 = 9
9 = 9
Уравнения верно решены и проверены.