Question

E urgent! Va rog frumos sa ma ajutati! In ∆ABC cu m(90°) se stie ca AB =3AC si BC =12cm. Calculati perimetrul ∆ABC.

Answer 1

teorema lui Pitagora
BC²=AB²+AC²
144=(3AC)²+AC²
144=9AC²+AC²
144=10AC²
AC²=144/10
AC=12/√10=(12√10)/10=(6√10)/5
AB=(18√10)/5
BC=12
P=AB+AC+BC=(18√10)/5+(6√10)/5+12=(24√10)/5+12