P dreptungi=2(a+b)
a/b=1,5=3/2 => a/3=b/2=(a+b)/(3+2)=(a+b)/5=(2a+2b)/10=80/10=8(cm)
=> a=3·8=24(cm)
si b=2·8=16(cm)
Sau:
a/3=b/2=k
=> a=3k si b=2k
Inlocuim:
2(3k+2k)=80cm |:2
5k=40cm |:5
k=8cm => a=3·8=24(cm)
Si b=2·8=16(cm)
Laturile dreptunghiului au lungimile de 24cm si 16cm
