Copyright 2013 Davitily

Find a Missing Side Using the Law of Cosines B Step 1: Apply the Law of Cosines to the triangle. Step 2: Select which formula to use. Step 3: Solve for the unknown. a b C a 2 = b 2 + c 2 −2bc⋅cos A b 2 = a 2 + c 2 −2ac⋅cos B c 2 = a 2 + b 2 −2ab⋅cos C a 2 = 19 2 + 17 2 −2 19 17 ⋅cos 49.9 o Step 1: Apply the Law of Cosines to the triangle. a 2 =361+289−646⋅cos 49.9 o Step 2: Select which formula to use. Step 3: Solve for the unknown. a 2 =361+289−416.10 a 2 =233.9 a= 233.9 =15.294=15.3

For more practice, visit www.mathproblemgenerator.com