Notez cu a,b,c lungimile laturilor triunghiului.
Avem: [tex] \frac{a}{3} =\frac{b}{5} = \frac{c}{7} [/tex] si a+b+c=360 (din datele problemei).
Utilizand rapoarte derivate, obtinem:
[tex] \frac{a}{3}= \frac{b}{5}= \frac{c}{7}= \frac{a+b+c}{3+5+7}= \frac{360}{15} = 24[/tex]
[tex] \frac{a}{3}=24 => a=72 (cm) [/tex]
[tex] \frac{b}{5}=24 => b=120(cm) [/tex]
[tex] \frac{c}{7}=24 => c=168(cm) [/tex]
