Răspuns:
P=2(L+l)
P=60m
L=2l
60=2(2l+l)
60:2=3l=>l=30:3=>l=10m ltimea
L=2·10=>L=20m lungimea
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L=5l
60=2(5l+l)
30=6l=>l=30:6=>l=5m latimea
L=5·5=>L=25m lungimea