Main content
Learn
Special right triangles intro (part 1)Special right triangles intro (part 2)30-60-90 triangle example problemSpecial right triangles proof (part 1)Special right triangles proof (part 2)Area of a regular hexagonSpecial right triangles review
Learn
Hypotenuse, opposite, and adjacentIntro to the trigonometric ratiosTrigonometric ratios in right trianglesTrigonometric ratios in right triangles
Learn
Solving for a side in right triangles with trigonometrySolving for a side in right triangles with trigonometry
Learn
Right triangle word problemAngles of elevation and depressionRight triangle trigonometry review
Learn
Triangle similarity & the trigonometric ratiosTrig challenge problem: verify identitiesTrig challenge problem: trig values & side ratios
Learn
Sine & cosine of complementary anglesUsing complementary anglesTrig word problem: complementary angles
Learn
Reciprocal trig ratiosFinding reciprocal trig ratiosUsing reciprocal trig ratiosTrigonometric ratios review
Learn
Solving for a side with the law of sinesSolving for an angle with the law of sinesProof of the law of sines
Learn
Solving for a side with the law of cosinesSolving for an angle with the law of cosinesProof of the law of cosines
Learn
Trig word problem: starsLaws of sines and cosines review
Identify your areas for growth in these lessons:
Test your understanding of Trigonometry with these 9 questions.

About this unit

Triangles are not always right (although they are never wrong), but when they are it opens up an exciting world of possibilities. Not only are right triangles cool in their own right (pun intended), they are the basis of very important ideas in analytic geometry (the distance between two points in space) and trigonometry.