CK-12 Foundation
Ck 12: Determination of Unknown Angles Using Law of Cosines
[Free Registration/Login may be required to access all resource tools.] Find an unknown angle of a side side side triangle using the Law of Cosines.
CK-12 Foundation
Ck 12: Trigonometry: Heron's Formula
[Free Registration/Login may be required to access all resource tools.] Find the area of a triangle when all three sides are known.