This week in Precalculus 11, we learned about Sine Law. You use Sine Law when you have an angle and a side that are opposite from the each other in a triangle.

There are two Sine Law equations:

The first one is for when you’re missing the angle.

The second equation is for when you’re missing the side.

In this example, you need to find the side BC, which is also side a because the angle opposite from it is angle A.

When solving, you can only use 2/3 of the fractions given.