Oswego City School District
Regents Exam Prep Center: Geometry Vocabulary Resources
A list of geometry definitions and a matching activity.
Sophia Learning
Sophia: Equilateral Triangle Interior Angles Practice Problems: Lesson 5
This lesson will provide practice problems that involve solving for unknown angle and side measures of equilateral triangles. It is 5 of 5 in the series titled "Equilateral Triangle Interior Angles Practice Problems."
Illustrative Mathematics
Illustrative Mathematics: G Co Are the Triangles Congruent?
In each of the following diagrams, two triangles are shaded. Based on the information given about each diagram, decide whether there is enough information to prove that the two triangles are congruent. Aligns with G-CO.B.
Texas Instruments
Texas Instruments: Investigate Triangles and Congruence
Students can use the TI-84 Plus family with Cabri Jr. to prove triangle congruence with SSA.
Illustrative Mathematics
Illustrative Mathematics: G Co Showing a Triangle Congruence: The General Case
Given distinct, congruent triangles, students are asked to show that congruence can always be shown with one, two, or three rigid motions. Aligns with G-CO.A.5.
Illustrative Mathematics
Illustrative Mathematics: G Co When Does Ssa Determine Triangle Congruence?
In this task, we are told that two triangles share two sets of congruent sides and one pair of congruent angles and that these two triangles must be congruent based on the reasoning given. Students are asked to analyze this reasoning to...
CK-12 Foundation
Ck 12: Congruent Triangles
[Free Registration/Login Required] Students explore the concept of congruent triangles by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more about...
Illustrative Mathematics
Illustrative Mathematics: G Co Showing a Triangle Congruence: A Particular Case
Given two congruent triangles, students are asked to analyze the effects of different transformations. Aligns with G-CO.A.5.
Math Open Reference
Math Open Reference: Congruent Triangles
A complete reference guide to congruent triangles. It provides definitions, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
Texas Instruments
Texas Instruments: Sas Triangle Congruence
This activity will help students visualize the construction of congruent triangles and conceptualize properties through measurement and movement of their construction. Students will need access to the TI-84 Plus Family.
Illustrative Mathematics
Illustrative Mathematics: 8.g Triangle Congruence With Coordinates
In this task, 8th graders explore congruence and transformations of two triangles on a coordinate grid. Aligns with 8.G.A.2.
Oswego City School District
Regents Exam Prep Center: Organizing and Venn Diagrams With Congruent Triangles
As a resource for teachers, an activity of how to connect Venn Diagrams with the five methods of proving triangles congruent - SSS, SAS, ASA, AAS, HL - is explained.
Texas Instruments
Texas Instruments: Isosceles Triangle
In this activity, students construct isosceles and equilateral triangles. They discover that if two sides of a triangle are congruent, then the angles opposite them are congruent. They understand that an equilateral triangle is also...
CK-12 Foundation
Ck 12: Congruence Statements
[Free Registration/Login Required] Students explore the concept of congruence statements by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more about...
Illustrative Mathematics
Illustrative Mathematics: G Srt Joining Two Midpoints of Sides of a Triangle
In this task, students must prove that angles and triangles are congruent and that a parallel line passes through the midpoints of two sides of the larger triangle. Aligns with G-SRT.B.4.
Illustrative Mathematics
Illustrative Mathematics: G Gpe, G Srt Finding Triangle Coordinates
Given a picture of a triangle on a coordinate grid, students are asked to find the coordinates of points which divide line segments in a given ratio. Aligns with G-GPE.B.6 and G-SRT.B.5.
University of Saskatchewan (Canada)
University of Saskatchewan: Triangles
This site from the University of Saskatchewan provides an explanation of similar triangles, the Pythagorean theorem, and the distance between arbitrary points in a plane. Example problems for each of these concepts are provided.
Science Struck
Science Struck: Similarity Statement in Geometry With Examples
Models how to write a similarity statement about different types of triangles and quadrilaterals.
ClassFlow
Class Flow: Congruency
[Free Registration/Login Required] Here are many variations of congruent triangles displayed for students to test their knowledge.
Illustrative Mathematics
Illustrative Mathematics: G Co Why Does Sas Work?
In this task, students must explain the given reasoning for why triangle ABC is congruent to triangle DEF using the language of reflections. Aligns with G-CO.B.8.
Illustrative Mathematics
Illustrative Mathematics: G Srt Extensions, Bisections, Dissections in Rectangle
For this task, learners must draw a diagram from a verbal description and use their understanding of similar triangles to find the area of a quadrilateral. Aligns with G-SRT.B.5.
Sophia Learning
Sophia: Triangle Congruence Theorem (Hl): Lesson 5
This lesson will present the Hypotenuse-Leg Triangle Congruence Theorem. It is 5 of 5 in the series titled "Triangle Congruence Theorem (HL)."
Homeschool Math
Homeschool Math: Area of Right Triangles
This lesson presents the idea that the area of any right triangle is exactly half of a certain rectangle, and contains varied exercises for students.
Illustrative Mathematics
Illustrative Mathematics: G Srt Finding the Area of an Equilateral Triangle
This task examines how to calculate the area of an equilateral triangle two ways: using triangle congruence and using trigonometric ratios. Aligns with G-CO.C.10 and G-SRT.C.