Question

AB=6CM AC= 12cm
calculate the length of CD

Answer 1

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

Answer 2

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