tolong ya kk. terima kasih

Sin C = AB/AC

Sin 30° = AB/18
1/2 = AB/18
AB = 9 cm

Maka :

(BC)² = 18² - 9²
          = 324 - 81
(BC)²  = 243
BC = √243
      = √(81.3)
      = 9√3 cm ... ( D )


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→ Matematika
Kelas : 8
KTSP 2006

Jawaban.

AB = 1/2 = ?/18
AB = 18 ÷ 2 × 1 = 9 cm

Phytagoras

BC = √ ( 18² - 9² )
BC = √ ( 324 - 81 )
BC = √ 243
BC = √ 81.3 = 9√3 cm