Răspuns:
Salut
AB=a
AC=b
BC=c
a+b+c=60
5,12,13=a/5=b/12=c/13=k =>a=5k
b=12k
c=13k
5k+12k+13k=60
17k+13k=60
30k=60
k=2
a=5•2=10
b=12•2=24
c=13•2=26
Deci:
AB=10cm
AC=24cm
BC=26cm
BC²=AB²+AC²
26²=10²+24²
676=100+576
676=676 Propozitie adevarata.
Triunghiul ∆ABC este dreptunghic.
==evergreen==