1)m(B)=180°-m(A)-m(C)=30°
m(B)=30°
m(A)=90° → (din amandoua) AC=BC/2
m(DAC)=180°-m(C)-m(D)=30°
m(DAB)=180°-m(B)-m(D)=60°
m(D)=90°
m(B)=30° →AD=AB/2
AD=4 cm
2)m(DAC)=30°
m(D)=90°→
DC=AC/2=BC/4
BD+DC=BC
BD=BC-DC
BD=BC-BC/4
BD=3•BC/4
DC=BC/4
4BD=3BC
4DC=BC
4BD=4•3DC
BD=3 DC
Spee că ai înțeles. Succes la școală!!!
