tolong dijawab cepet

6) AB/(sin C) = AC/(sin B)
10/(sin C) = 12/(4/5)
12 sin C = 8
Sin C = 8/12 = 2/3 = de/mi
sa = √(3^2 - 2^2) = √(9 - 4) = √5
Cos C = sa/mi = √5/3 = (1/3)√5

8) <¢ = Sin ¢ = sin B = 1/3 = de/mi => sa = √(3^2 - 1^2) = √(9 - 1) = √8 = 2√2
Cos B = sa/mi = 2√2 / 3
AC^2 = AB^2 + BC^2 - 2 . AB . BC . Cos B
AC^2 = (2√2)^2 + 2^2 - 2 . 2√2 . 2 . (2√2)/3
AC^2 = 8 + 4 - 32/3
AC^2 = 4/3
AC = √(4/3) = 2/√3 . √3/√3 = 2√3/3 = (2/3)√3