# right triangles   106 videos

• #### Triangle Side and Angle Inequalities

##### GeometryTriangles

How to determine the relationship between the side inequalities and angle inequalities in a triangle.

angles smallest to largest sides smallest to largest
• #### Area and Perimeter of Triangles

##### Pre-AlgebraIntroductory Geometry

Understanding why the area of a triangle is 1/2 base times height

• #### Similar Triangles

##### Pre-AlgebraIntroductory Geometry

Overview of similarity: congruent angles, proportional corresponding sides

• #### Civil Liberties 101

##### AP US GovernmentAP US Government Videos

How can we balance individual rights with the public good?

Bill of Rights civil liberties
• #### Proportional Segments Between Parallel Lines

##### GeometrySimilarity

How to prove two triangles are similar using a line parallel to a base.

parallel lines triangles similar triangles proportion
• #### Indirect Measurement

##### GeometrySimilarity

How to use similar triangles to measure the height of objects.

indirect measurement similar triangles measurement
• #### Pythagorean Theorem Proofs

##### GeometryPythagorean Theorem

How to prove the Pythagorean Theorem using Algebra to show the area of the smaller square plus the area of four triangles is equal to the area of the larger square.

right triangle area of a square binomial squared area of a triangle side leg hypotenuse
• #### Pythagorean Theorem Proofs

##### TrigonometryPythagorean Theorem

How to prove the Pythagorean Theorem using Algebra to show the area of the smaller square plus the area of four triangles is equal to the area of the larger square.

right triangle area of a square binomial squared area of a triangle side leg hypotenuse
• #### Similarity Shortcuts

##### GeometrySimilarity

How to determine if two triangles are similar using a shortcut.

similar triangles AA SAS SSS proportion congruence
• #### Using the Pythagorean Theorem to find a Missing Leg

##### GeometryPythagorean Theorem

How to use the Pythagorean Theorem to find a missing leg, given the length of the hypotenuse and a leg.

Pythagorean theorem leg hypotenuse right triangle
• #### Using the Pythagorean Theorem to find a Missing Leg

##### TrigonometryPythagorean Theorem

How to use the Pythagorean Theorem to find a missing leg, given the length of the hypotenuse and a leg.

Pythagorean theorem leg hypotenuse right triangle
• #### The Tangent Function

##### TrigonometryTrigonometric Functions

How to define the tangent function for all angles.

tangent right triangle trigonometry the unit circle
• #### The Tangent Function

##### PrecalculusTrigonometric Functions

How to define the tangent function for all angles.

tangent right triangle trigonometry the unit circle
• #### CPCTC

##### GeometryTriangles

How to use the principle that corresponding parts of congruent triangles are congruent, or CPCTC.

corresponding parts or congruent triangles proofs
• #### 3-D Solid Properties

##### GeometryVolume

How to label the parts of a prism, how to distinguish between an oblique and a right prism.

vertex bases face lateral face edge oblique prism right prism
• #### Angles: Types and Labeling

##### GeometryGeometry Building Blocks

How to label an angle and how to differentiate between acute, right, obtuse, and straight angles.

angle acute right obtuse straight vertex side
• #### SSS and SAS

##### GeometryTriangles

How to use the SAS and SSS shortcuts to determine the congruence of two triangles.

triangle congruence side side side side angle side
• #### ASA and AAS

##### GeometryTriangles

How to use the ASA and AAS shortcuts to determine the congruence of two triangles.

triangle congruence angle side angle angle angle side
• #### Constructing a Median

##### GeometryConstructions

How to define a median in a triangle.

midpoint vertex segment median
• #### Constructing the Orthocenter

##### GeometryConstructions

How to construct the orthocenter of a triangle.

point of concurrency orthocenter altitude construction