Răspuns :
A tr=AB•AC•sin A/2
AB=AC=6 cm
m(B)=m(C)=75
Rezulta m(A)=180-2•75=30
Rezulta A=6•6•1/2/2
A=18/2
A=9 cm^2
[tex]A_{\triangle ABC}=\frac{AB\cdot AC\cdot sinA}{2}[/tex]
m(<B) = 75°
m(<C) = m(<B) = 75°
m(<A) = 180° - (75°+75°) = 180° - 150° = 30°
sin A = sin 30 = 1/2
[tex]A_{\triangle ABC}=\frac{6\cdot6\cdot\frac{1}{2}}{2}=\frac{18}{2}=9[/tex]
m(<B) = 75°
m(<C) = m(<B) = 75°
m(<A) = 180° - (75°+75°) = 180° - 150° = 30°
sin A = sin 30 = 1/2
[tex]A_{\triangle ABC}=\frac{6\cdot6\cdot\frac{1}{2}}{2}=\frac{18}{2}=9[/tex]