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This page provides a list of educational videos related to Congruence. You can also use this page to find sample questions, apps, worksheets, lessons , infographics and presentations related to Congruence.
Reason about the triangle congruence postulates
By Khan Academy
There are some cases when SSA can imply triangle congruence, but not always. This is why it's not like the other triangle congruence postulates/criteria.
Finding area using similarity and congruence | Similarity | Geometry | Khan Academy
By Khan Academy
Example of using similarity and congruence to find the area of a triangle
Geometry - Triangle Congruence - SSS SAS ASA postulate through constructions.wmv
By Soowook Lee
Geometry - Triangle Congruence - SSS SAS ASA postulate through constructions.wmv
Reason about the triangle congruence postulates
By Khan Academy
Sal explains what it means for triangles to be congruent and what is a postulate/axiom. He also presents the SSS congruence postulate/criterion and its justification.
Triangle Congruence by SSS and SAS - How to Prove Triangles Congurent
By MrPilarski
YouTube presents Triangle Congruence by SSS and SAS - How to Prove Triangles Congurent, an educational video resource on math.
Recovering the Sequence of Transformations to Show Congruence or Similarity
By James Olsen
Directions: Two figures will be given. Determine if they are congruent or similar. Then state the sequence of transformations that exhibits the congruence or similarity. There is an error in this video!! In example 3, the first translation should be using vector BF (and not vector AF). This is aligned with the following Common Core State Standards for Mathematics: [8.G.2] Understand that a two-dimensional figure is congruent to another if the second can be obtained from the first by a sequence of rotations, reflections, and translations; given two congruent figures, describe a sequence that exhibits the congruence between them. [8.G.4] Understand that a two-dimensional figure is similar to another if the second can be obtained from the first by a sequence of rotations, reflections, translations, and dilations; given two similar two- dimensional figures, describe a sequence that exhibits the similarity between them. [G.CO.5] Given a geometric figure and a rotation, reflection, or translation, draw the transformed figure using, e.g., graph paper, tracing paper, or geometry software. Specify a sequence of transformations that will carry a given figure onto another. [G.SRT.2] Given two figures, use the definition of similarity in terms of similarity transformations to decide if they are similar
Other triangle congruence postulates | Congruence | Geometry | Khan Academy
By Khan Academy
SSS, SAS, ASA and AAS postulates for congruent triangles. Showing AAA is only good for similarity and SSA is good for neither
Perform sequences of transformations and determine congruence
By Khan Academy
Sal maps a given quadrilateral onto another using a translation, a dilation, and a reflection. The quadrilaterals are not congruent because a dilation was used.
Reason about the triangle congruence postulates
By Khan Academy
Sal introduces and justifies the SSS, SAS, ASA and AAS postulates for congruent triangles. He also shows that AAA is only good for similarity. For SSA, better to watch next video.
Perform sequences of transformations and determine congruence
By Khan Academy
Sal reflects and then translates a given pentagon, and determines whether the resulting figure is congruent to the source figure.
Similar triangles 1
By Khan Academy
Sal reviews all the different ways we can determine that two triangles are similar. This is similar to the congruence criteria, only for similarity!
Solving problems with similar and congruent triangles
By Khan Academy
Sal uses the similarity of triangles and the congruence of others in this multi-step problem to find the area of a polygon.
Similar triangles 2
By Khan Academy
Sal reviews all the different ways we can determine that two triangles are similar. This is similar to the congruence criteria, only for similarity!
Algebraic Proofs in Geometry
By Sir Tyler Tarver
This video review the properties of equality that are used to write algebraic proofs. It identifies properties of equality and congruence.
Congruent Triangle Proof Example
By Khan Academy
Proving that a point is the midpoint via triangle congruency. All Khan Academy content is available for free at www.khanacademy.org
Determine whether two triangles are congruent
By Khan Academy
Sal explains what it means for triangles to be congruent and what is a postulate/axiom. He also presents the SSS congruence postulate/criterion and its justification.
Determine whether two triangles are congruent
By Khan Academy
Sal explains what it means for triangles to be congruent and what is a postulate/axiom. He also presents the SSS congruence postulate/criterion and its justification.
Determine whether two triangles are congruent
By Khan Academy
Sal explains what it means for triangles to be congruent and what is a postulate/axiom. He also presents the SSS congruence postulate/criterion and its justification.
Congruent legs and base angles of isosceles triangles | Congruence | Geometry | Khan Academy
By Khan Academy
Showing that congruent legs imply equal base angles and vice versa. All Khan Academy content is available for free at www.khanacademy.org
Another isosceles example problem | Congruence | Geometry | Khan Academy
By Khan Academy
Possible angles for an isosceles triangle. All Khan Academy content is available for free at www.khanacademy.org