This week we learned 9-3. Law of Sines. You use law of sines when you cant use SOHCAHTOA to solve the triangle.
you can only use law of sines when you have an angle and opposite leg value that you know.

Formula for Law of sines:
sin(angle) / opposite leg=sin(angle2) / opposite leg 2
you cross multiply to solve.

EXAMPLE:
A=45 degrees B=60 degrees a=14
**first you must draw your triangle!
subtract 45 and 60 from 180 to find your 3rd angle.
C=75 degrees.
set it up into your formula.
sin(75) / 14=sin(45) / x.
cross multiply.
xsin75=14sin45
set it up to divide.
14sin45 / sin 75.
plug it into your calculator and you should get an answer of:
x=10.249

Its really not that hard to work these problems. The hardest part is taking the points and making a triangle to solve from word problems.