Răspuns:
a) a+b+c+d+e+f=57
a,b=consecutive pare
c+d=12
e-f=21=>e=f+21
d=3*c
c*4=12=>c=3
d=3*3
d=9
21:3=7, e=7, f=7x4=28, f=28, 28-7=21 diferenta
a+a+2+3+9+7+28=57
a*2=8
a=4
b=a+2
b=6
b) a=b*3+7
a-40=b-5=>a-35=b=>a=b+35
b*3+7=b+35
b*3=b+28
b*2=28
b=14
a=49
Sper ca te-am ajutat.