# triangle   83 videos

• #### Area of Triangles

##### GeometryArea

How to derive the area of a triangle formula using the rectangle area formula.

area triangles rectangles altitude
• #### Types of Triangles

##### GeometryGeometry Building Blocks

How to classify a triangle based on its side lengths and angle measures.

equiangular equilateral isosceles right acute obtuse triangles
• #### Triangle Angle Sum

##### GeometryTriangles

How to apply the triangle angle sum theorem.

triangle angle sum theorem 180 degrees
• #### Similar Triangles in Circles and Right Triangles

##### GeometrySimilarity

How to determine if two triangles in a circle are similar and how to prove that three similar triangles exist in a right triangle with an altitude.

similar inscribed angles intercepted arc right angle circle
• #### Pascal's Triangle

##### Algebra 2Polynomials

How to use Pascal's triangle.

zero product property factoring constant
• #### Pascal's Triangle

##### PrecalculusTopics in Discrete Math

How to use Pascal's triangle.

zero product property factoring constant
• #### Using Sine to Calculate the Area of a Triangle

##### GeometryBasic Trigonometry

How to calculate the area of any triangle using two sides and an included angle.

area of a triangle sine
• #### Using Sine to Calculate the Area of a Triangle

##### TrigonometryBasic Trigonometry

How to calculate the area of any triangle using two sides and an included angle.

area of a triangle sine
• #### Using Sine to Calculate the Area of a Triangle

##### PrecalculusBasic Trigonometry

How to calculate the area of any triangle using two sides and an included angle.

area of a triangle sine
• #### Special Isosceles Triangle Properties

##### GeometryTriangles

How to identify a segment from the vertex angle in an isosceles triangle to the opposite side.

isosceles triangle angle bisector altitude median
• #### Triangle Midsegment Properties

##### GeometryPolygons

How to define a triangle midsegment and describe its special properties.

midsegment triangle parallel bases midpoint third side
• #### Corresponding Parts of Similar Triangles

##### GeometrySimilarity

How to relate corresponding altitudes, medians and angle bisectors in similar triangles.

similar triangles altitude median angle bisector proportional
• #### Iron Triangles

##### AP US GovernmentAP US Government Videos

How is public policy made? Who controls the bureaucracy?

Iron triangles bureaucracy
• #### 30-60-90 Triangles

##### GeometryPythagorean Theorem

How to find the legs and hypotenuse in 30-60-90 triangles when given: the short leg, the long leg, or the hypotenuse.

right triangle short leg long leg hypotenuse
• #### 30-60-90 Triangles

##### TrigonometryPythagorean Theorem

How to find the legs and hypotenuse in 30-60-90 triangles when given: the short leg, the long leg, or the hypotenuse.

right triangle short leg long leg hypotenuse
• #### Constructing a Triangle Midsegment

##### GeometryConstructions

How to define a midsegment in a triangle.

midpoint segment median
• #### 45-45-90 Triangles

##### GeometryPythagorean Theorem

How to find the length of a leg or hypotenuse in a 45-45-90 triangle using the Pythagorean Theorem.

isosceles right triangle leg hypotenuse Pythagorean theorem square root
• #### 45-45-90 Triangles

##### TrigonometryPythagorean Theorem

How to find the length of a leg or hypotenuse in a 45-45-90 triangle using the Pythagorean Theorem.

isosceles right triangle leg hypotenuse Pythagorean theorem square root
• #### Isosceles Triangles

##### GeometryTriangles

How to define isosceles triangles, their components and how to determine their properties.

vertex angle leg base base angle converse remote interior angles
• #### Triangle Side Inequalities

##### GeometryTriangles

How to determine the triangle side inequalities.

shortest distance side length inequalities