This week we didn't really learn new stuff, we just took a test tuesday through friday and reviewed the chapter on monday.
But anyways...
One of the things on the test was law of sines.
Law of sines only works when you have an angle with a side opposite to that angle, and you also need either another angle or another side. So, what you do is set up for the formula...
sintheta/opposite leg = sintheta/opposite leg
... then you cross mulitply to solve for either the missing angle or the missing side
For example:
If you had a triangle ABC and angle A is 28 degrees and side a is 8 and side c is 12.
You plug it into the formula as..
sin 28/8 = sinC/12
Then, by cross multipling you get.
12sin28 = 8sinC
Dividing by 8
you then get 12sin28/8 = sinC
Then you take the inverse
C = sin ^-1 (12 sin28/8)
so angle C = 44.77 degrees
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