Номер 90.Спасибо заранее.
BC=24 cm cos A =0,75 AB = BC = 24 cm AH = AB*cos A = 24*0,75 = 18 cm AC = 2*AH = 36 cm ------------------ AC = 42 cm cos A = 0,6 AH = AC/2 = 42/2 = 21 cm AH/AB = cos A AB = AH/cos A = 21/0,6 = 21*10/6 = 7*5 = 35 cm