Răspuns :
a-b= 2*7
a-b=14 => a=14+b
a+b= 30 (inlocuim) 14+b+b=30
14+2b=30
2b=30-14
2b=16
b=8
deci a=14+8=22
a-b=14 => a=14+b
a+b= 30 (inlocuim) 14+b+b=30
14+2b=30
2b=30-14
2b=16
b=8
deci a=14+8=22
a+b=30. a-b=7×2. a-b=14. a=|__|+14|. b=|__|. 30-14=16. 16:2=8 (b). 8+14=22 (a). Verificare: 22+8=30. 22-8=14.