Oblicz pole i obwód trójkąta ABC, wiedziac, że AC = BC = 12cm i miara kąta ACB = 120°   Prosze o pomoc ;)

             C                            skoro ∢ ACB=120°to ∢ACD=60°a ∢CAD 30°                                           |DC|                 1                    1                                           ------ = sin30°= ---    =>    DC= ---AC=6                                                       |AC|                 2                    2  A         D          B                                           |AD|                √3                 √3 P=1/2*a*h                           ------= cos 30°= ---   =>    AD= ---AC=6√3                                           |AC|                 2                   2 AD=6√3 to AB=12√3 P=1/2*12√3*6=36√3 Obw=12√3+12+12=12√3+24