Question

Tolong jawab nomor 4 pakai cara ya

Answer 1

Verified answer

Kelas 10 Matematika
Bab Trigonometri

Luas = 12 √3
1/2 . a . b . sin C = 12√3
1/2 . 8 . 6 . sin C = 12√3
sin C = (12 √3)/24
sin C = 1/2 √3
C = 60° atau 120°

c = √(a² + b² - 2 . a . b . cos C)
c = √(8² + 6² - 2 . 8 . 6 . cos 60°)
c = √(64 + 36 - 2 . 48 . 1/2)
c = √(100 - 48)
c = √52
c = √(4 . 13)
c = 2 √13 cm

atau

c = √(a² + b² - 2 . a . b . cos C)
c = √(8² + 6² - 2 . 8 . 6 . cos 120°)
c = √(64 + 36 - 2 . 48 . (-1/2))
c = √(100 + 48)
c = √148
c = √(4 . 37)
c = 2 √37 cm

Maka, c = 2√13 cm atau 2√37 cm