Question

ada yang bisa bantuu kak butuh banget :(​

Answer 1

Penjelasan dengan langkah-langkah:

cos α = 3/5

BC = 12 cm

misal jarak titik C ke alas AB = O

siku-siku di C

sin²α + cos²α = 1

sin²α + (3/5)² = 1

sin²α + 9/25 = 1

sin²α = 1 - 9/25

sin²α = 16/25

sin α = √(16/25)

sin α = 4/5

sin α = BC / AB

4/5 = 12/AB

4AB = 60

AB = 60 / 4

AB = 15 cm

AC = √(AB² - BC²)

AC = √(15² - 12²)

AC = √(225 - 144)

AC = √81

AC = 9 cm

rumus dimensi tiga :

1/2 x AC x BC = 1/2 x AB x O

1/2 x 9 x 12 = 1/2 x 15 x O

9 x 6 = 15/2 (O)

54 = 15/2 (O)

108 = 15O

O = 108 / 15

O = 36/5

O = 7,2 cm