Question

DESPERATE FOR EXPLANATION PLEASE HELP

Answer 1

This one is the Law of Sines again.

The Law of Sines relies on the standard labeling of triangle ABC with vertices A, B, and C and respective opposite sides of a, b and c. Then

$\dfrac{a}{\sin A} = \dfrac{b}{\sin B} = \dfrac{c}{\sin C}$

Here we have A=150 degrees (opposite side a), b= 10 cm and B = 12 degrees. We seek a.

So we need the first equation of the Law of Sines:

$\dfrac{a}{\sin A} = \dfrac{b}{\sin B}$

$a = \dfrac{b \sin A }{\sin B}$

$a = \dfrac{10 \sin 150}{\sin 12} \approx 28.0$