Răspuns :
Salut,
∆ ABC ~ ∆ DEF
BC = 12 cm
EF = 18 cm
DF = 15 cm
AB/DE = BC/EF = AC/DF
AB/DE = 12/18 = AC/15
AB/DE = 2/3 = AC/15
AC/15 = 2/3
AC = 2•15/3
AC = 2•5
AC = 10 cm.
AB/DE = 2/3
AC/15 = 10/15 = 2/3 → BC/EF = AC/DF.
AB = 2DE/3.
∆ ABC ~ ∆ DEF
BC = 12 cm
EF = 18 cm
DF = 15 cm
AB/DE = BC/EF = AC/DF
AB/DE = 12/18 = AC/15
AB/DE = 2/3 = AC/15
AC/15 = 2/3
AC = 2•15/3
AC = 2•5
AC = 10 cm.
AB/DE = 2/3
AC/15 = 10/15 = 2/3 → BC/EF = AC/DF.
AB = 2DE/3.
scrie asa ' triunghiul ABC asemenea triunghiului DEF
BC= 12
EF- 18
DF - 15
AB AC BC AB AC 12
--- = ---- = ---- = ---- = ---- = ---
DE DF EF DE 15 18
luam ultimul raport si observam ca AC = 12x15/18 = 60/6=10cm
raportul de asemanare este egal cu 12/18 = 2/3
BC= 12
EF- 18
DF - 15
AB AC BC AB AC 12
--- = ---- = ---- = ---- = ---- = ---
DE DF EF DE 15 18
luam ultimul raport si observam ca AC = 12x15/18 = 60/6=10cm
raportul de asemanare este egal cu 12/18 = 2/3