Răspuns:
Explicație pas cu pas:
AM/MB=3/2 ; ⇒AM= 3k ;MB =2K (AB=15)
AB=AM+MB =3k+2k=5k
15=5k ;⇒ k=15/5 =3
⇒AM=3k=3*3=9cm
MB=2k=2*3=6cm
verificam daca MNâ•‘BC
AM/AB=AN/AC=MN/BC
9/15 =18/30 ⇒9*30=18*15 ⇒270=270⇒MN║BC
AM/AB=MN/BC
9/15 =MN/25
MN=9*25/15 =15 cm
Pamn =AM+MN+AN =9+15+18=42 cm