AB=6cm AC=12cm
AC² = AB + BC²
12² = 6² + CB²
CB² = 12² - 6²
CB² = 144 - 36
CB² = 108
CB = √ 108 cm.
sin 55° = CB / CD
0.81915 = √108 / CD
CD = 10.392 / 0.81915
CD = 12.686 cm
Answer:
Step-by-step explanation:
This was a question on mathswatch, so I’ve done this.
You need to round to 3 significant numbers
AB=6cm AC=12cm
AC² = AB + BC²
12² = 6² + CB²
CB² = 12² - 6²
CB² = 144 - 36
CB² = 108
CB = √ 108 cm.
sin 55° = CB / CD
0.81915 = √108 / CD
CD = 10.392 / 0.81915
CD = 12.686 cm
CD = 12.7 cm
