Răspuns:
a) AM/AB=AN/AC
2/8=5/20
40=40 ADEVAR =>MN||BC
b) AN=10-8=2
AM/AB=AN/AC
3/15=2/10
30=30 ADEVAR =>MN||BC
c)AB=14 AC=30
AM/AB=AN/AC
6/14=10/30
180=140 fals. MN nu e paralel cu BC
d) AN=30-24=6
AM/AB=AN/AC
4/24=6/30
144=120 fals. MN nu e paralel cu BC