Lessons for G.SRT.D.11
Law of cosinesPlacing the triangle on the coordinate plane and applying the distance formula to the third vertex gives the law.Lesson
Law of sinesAn altitude splits the triangle into two right triangles sharing a height, and equating the heights gives the law.Lesson
The ambiguous caseThe altitude from the given angle decides whether zero, one or two triangles can close.Lesson
Laws of sines and cosinesTrig for triangles that are not right.Lesson
Applications of oblique trianglesLocating a point by measuring the angles to it from the two ends of a known baseline.Lesson
Printable Worksheets
Law of cosines worksheet (PDF)Printable worksheet with answer keyPreview
Law of sines worksheet (PDF)Printable worksheet with answer keyPreview
The ambiguous case worksheet (PDF)Printable worksheet with answer keyPreview
Applications of oblique triangles worksheet (PDF)Printable worksheet with answer keyPreview