Examples using sine rule

You can use the sine rule (If you can remember it – but why try) here it is anyway:

Example 1

Find the length of `x` in the following diagram?

Solution:

The sine rule: `a/sinA=b/sinB=c/sinC` 

In a triangle that looks like:

Therefore use:

Answer: `x=7.959`

Example 2

Find angle A

Solution:

The sine rule: `a/sinA=b/sinB=c/sinC`

In a triangle that looks like:

Therefore Use:

 Or

Answer: `A=48.61^@`