Question

ajutatima varog frumos la ex 4 si 5 varog urgenttt plizzz​

Answer 1

Ex 4:

AB=20cm

MB=4cm  

AM=AB-MB-20-4=16cm

Daca MN || BC => M,N sunt la distante egale pe dreptele AB,AC => AM=AN; MB=NC => NC=MB=4cm

Ex 5:

AB=18cm

AM=7cm

MN=4cm

Triunghiurile ABC si MNC sunt asemenea => $\frac{MN}{AB} = \frac{AM}{AC}= \frac{NB}{BC}=>\frac{4}{18} = \frac{7}{AC}=\frac{NB}{BC} => AC=\frac{18*7}{4} => AC=31.5cm$