Răspuns:
1. AB/BC=8/5
5AB=8BC
AB=8BC/5
P=2AB+2BC
130=16BC/5+2BC
130=16BC/5+10BC/5
26BC/5=130
26BC=130×5
26BC=650
BC=650÷26
BC=25
AB=8×25/5
AB=40
2