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Unit: Right triangles & trigonometry

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Pythagorean theorem

Learn
Getting ready for right triangles and trigonometry
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Pythagorean theorem in 3D
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Pythagorean theorem with isosceles triangle
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Multi-step word problem with Pythagorean theorem
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Practice
Pythagorean theorem in 3DGet 3 of 4 questions to level up!
Pythagorean theorem challengeGet 3 of 4 questions to level up!

Pythagorean theorem proofs

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Garfield's proof of the Pythagorean theorem
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Bhaskara's proof of the Pythagorean theorem
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Pythagorean theorem proof using similarity
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Another Pythagorean theorem proof
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Special right triangles

Learn
Special right triangles proof (part 1)
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Special right triangles proof (part 2)
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30-60-90 triangle example problem
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Area of a regular hexagon
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Special right triangles review
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Practice
Special right trianglesGet 3 of 4 questions to level up!

Quiz 1

Level up on the above skills and collect up to 300 Mastery points

Ratios in right triangles

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Hypotenuse, opposite, and adjacent
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Side ratios in right triangles as a function of the angles
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Using similarity to estimate ratio between side lengths
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Using right triangle ratios to approximate angle measure
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Practice
Use ratios in right trianglesGet 3 of 4 questions to level up!

Introduction to the trigonometric ratios

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Triangle similarity & the trigonometric ratios
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Trigonometric ratios in right triangles
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Trigonometric ratios in right triangles
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Practice
Trigonometric ratios in right trianglesGet 3 of 4 questions to level up!

Solving for a side in a right triangle using the trigonometric ratios

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Solving for a side in right triangles with trigonometry
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Solving for a side in right triangles with trigonometry
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Practice
Solve for a side in right trianglesGet 3 of 4 questions to level up!

Solving for an angle in a right triangle using the trigonometric ratios

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Intro to inverse trig functions
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Practice
Solve for an angle in right trianglesGet 3 of 4 questions to level up!

Quiz 2

Level up on the above skills and collect up to 400 Mastery points

Sine & cosine of complementary angles

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Sine & cosine of complementary angles
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Using complementary angles
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Trig word problem: complementary angles
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Trig challenge problem: trig values & side ratios
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Practice
Relate ratios in right trianglesGet 3 of 4 questions to level up!

Modeling with right triangles

Learn
Right triangle word problem
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Angles of elevation and depression
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Right triangle trigonometry review
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Practice
Right triangle trigonometry word problemsGet 3 of 4 questions to level up!

Quiz 3

Level up on the above skills and collect up to 200 Mastery points
Up next for you:

Unit test

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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.