This week in pre-calc 11, we learned about sine law and how it can be used to find an angle or a side of a triangle. The law states that in any triangle the ratio of the sides of a triangle and their opposite sine angles are equivalent to each other.

Here is the formula and location of the variables.

Let’s now try an example.

In this example it’s asking us to use the sine law to find side b.

And from our given values we only have Sine A and B. Then we plug the given values into the formula.

Then we solve for the side (b) rearranging algebraically as needed, giving us the answer.

Now let’s try another example.

In this example it is asking us to find angle A.

And from our given values we only have to use Sine Sine A and C. Then we plug in our values again like last time.

Then we solve for the side C rearranging algebraically as needed, giving us the answer.