Tolong dibantu ya, saya kurang paham, oke
Diketahui:
- ∠CAB = 30°
- ∠ACB = 85°
- ∠ABD = 180°
- ∠CAB + ∠ACB + ∠CBA = 180°
Pertama cari ∠CBA
∠CAB + ∠ACB + ∠CBA = 180°
∠CBA = 180° – (∠CAB + ∠ACB)
∠CBA = 180° – (30° + 85°)
∠CBA = 180° – 115°
∠CBA = 65°
Kedua cari ∠CBD
∠CBA + ∠CBD = ∠ABD
∠CBD = ∠ABD – ∠CBA
∠CBD = 180° – 65°
∠CBD = 115°
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