Question

Se considera dreptunghiul DEFG,in care m(

Answer 1

a)m(GDF)=2*m(EDF)⇒x+2x=90⇒3x=90⇒x=30°⇒m(GDF)=30° si m(EDF)=60°
Deci m(EFD)=30°
Dupa th unghiului de 30° aflam DF:
DE=1/2*DF⇒DF=2*DE⇒DF=2*5$\sqrt{6}$ =10$\sqrt{6}$
Acum folosim teorema lui Pitagora
EF²=DF²-DE²
EF²=(10$\sqrt{6}$)²-(5$\sqrt{6}$)²
EF²=100*6-25*6
EF²=600-150
EF²=450
EF=15$\sqrt{2}$

Adr=L*l⇒Adr=5$\sqrt{6}$ *15$\sqrt{2}$ =150$\sqrt{3}$