b = 90 - 18 = 72
x= 80-25 = 55
Ответ:
b=72. x=50.
Пошаговое объяснение:
b+18=90;
b=90-18;
b=72.
25+x=80;
x=80-25;
x=50.
1) 3 11/15 ≤ х/15 ≤ 4
56/15 ≤ х/15 ≤ 60/15
х = 56; 57; 58; 59; 60.
2) 3 1/8 ≤ 25х ≤ 8 1/3
25/8 ≤ 25х ≤25/3
1/8 ≤ х ≤ 1/3
3/24 ≤ х ≤ 8/24
х = 3; 4; 5; 6; 7; 8.