Răspuns :
teorema lui pitagora in Δ ABC (Ac=diagonala)
AC²=AB²+BC²=>AC²= 2AB² (AB=BC)
36=2AB²=> AB=√18=> AB=3√2=l
A patrat= l² => A=18 cm²
AC²=AB²+BC²=>AC²= 2AB² (AB=BC)
36=2AB²=> AB=√18=> AB=3√2=l
A patrat= l² => A=18 cm²