1) При a=5:15+5-13 = 7b-12+8 = 32-12+8 = 28
2) При a=10:15+10-13 = 12b-12+8 = 32-12+8 = 28
3) При a=20:15+20-13 = 22b-12+8 = 43-12+8 = 39
4) При a=30:15+30-13 = 32b-12+8 = 52-12+8 = 48
1) При a=5:
15+5-13 = 7
b-12+8 = 32-12+8 = 28
2) При a=10:
15+10-13 = 12
b-12+8 = 32-12+8 = 28
3) При a=20:
15+20-13 = 22
b-12+8 = 43-12+8 = 39
4) При a=30:
15+30-13 = 32
b-12+8 = 52-12+8 = 48