Răspuns:
1. a+b=13
a-b=9
a+b+a-b=22
2a=22
a=11
b=13-11
b=2
2. g = numarul gastelor
c = numarul caprelor
g + c = 41
2g + 4c = 126
g = 41 - c
2(41 - c) + 4c = 126
82 - 2c + 4c = 126
2c = 126 - 82 = 44
c = 44 : 2 = 22 capre
g = 41 - 22 = 19 gaste
3. L cerc = 2πR
P=4R
L cerc-1=P
2πR-1=4R
2πR-4R=1
2R(π-2)=1
R=1/2(π-2)=1/2(3,14-2)=1/2 x 1,14=0,43
R=0,43cm
