a-latime
b-lungime
P=2a+2b
P=2200m=10(b-a)
2a+2b=2200=10b-10a
2200-2a=2b
10b=2b×5
10b=5(2200-2a)
5(2200-2a)-10a=2200
5×2200-2×5a-10a=2200
11000-10a-10a=2200
11000-20a=2200
20a=11000-2200
20a=9800
a=9800÷20
a=490m
2a+2b=2200
2×490+2b=2200
980+2b=2200
2b=2200-980
2b=1220
b=1220÷2
b=610m
R: a=490m
b=610m