Solving Problems Involving Oblique Triangle

• Oblique triangle


  A triangle with no right angle
• Solving problems involving oblique triangles


  • Using the law of sines and the law of cosines
• Law of cosines


  c^2 = a^2 + b^2 - 2ab cos C
• Solving for sides and angles in oblique triangles

  • Using law of sines for SSA and SSS
  • Using law of cosines for SAS
• In an oblique triangle, if only two sides and the included angle are known (SAS), the law of cosines is used to solve for the third side
• In an oblique triangle, if three sides are known (SSS), the law of cosines is used to solve for the angles
• In an oblique triangle, if two sides and the non-included angle are known (SSA), the law of sines is used to solve for the remaining sides and angles
• Angle of depression


  The angle between the horizontal line of sight and the line of sight to an object that is below the observer
• Solving for distance between two divers and a shark

  Use law of sines to find the distances of the divers from the shark
• When solving for sides and angles in oblique triangles, the law of cosines is used for SAS and SSS, while the law of sines is used for SSA