Question

Ajutor dau coroana !​

Answer 1

Răspuns:

a) Triunghi isoscel => AB=AC

P= AB+AC+BC

AB+AB+ $\frac{6AB}{5}$=96     2*AB+$\frac{6AB}{5}$=96  aducem la acelasi numitor

10 AB+6AB= 96*5    16 AB= 96*5

AB= $\frac{96*5}{16}$= 6*5=30 cm   AB=AC=30 cm

BC= 96-2*30= 96-60=36 cm   BC=36 cm

b) m(ABC) + m(BAC) + m(ACB)=180 °

triunghi isoscel=> m(A) =m(B)  sau m(A)=m(C)

2*m(A)+m(C)=180°

BD= AC/2 =30/2=15 cm

sin (BAC)=$\frac{BD}{AB}$= $\frac{15}{30} =\frac{1}{2}$ => m(BAC)=30 °