West Contra Costa Unified School District
Investigating Similar Triangles
Let your use of the resource be in proportion to its usefulness. Pupils investigate similar triangles by measuring side lengths and considering given angle measures. The results of the investigation help develop generalizations about...
Education Development Center
Similar Triangles
Model geometric concepts through a hands-on approach. Learners apply similar triangle relationships to solve for an unknown side length. Before they find the solution, they describe the transformation to help identify corresponding sides.
Curated OER
Similar Triangles and Proportions
Pupils investigate similar triangles and proportions as they make conjectures about the length of sides of similar triangles. For this lesson, have your class construct similar triangles using Cabri Jr so that they share a common vertex.
Mathematics Vision Project
Similarity and Right Triangle Trigonometry
Starting with similar triangles and dilation factors, this unit quickly and thoroughly progresses into the world of right triangle features and trigonometric relationships. Presented in easy-to-attack modules with copious application...
Utah Education Network (UEN)
Finding Missing Lengths of Similar Triangles
Middle and high schoolers explore the properties of similar triangles. In this geometry lesson, pupils play a similarity basketball game, sketch similar triangles, and find the missing measures of similar figures. They find the height of...
EngageNY
Special Relationships Within Right Triangles—Dividing into Two Similar Sub-Triangles
Why are right triangles so special? Pupils begin their study of right triangles by examining similar right triangles. Verifying through proofs, scholars recognize the three similar right triangles formed by drawing the altitude. Once...
Curated OER
Similar Triangles - Applied Problems
Students differentiate between similar and congruent triangles. In this geometry lesson, students identify the angles of triangles using the similarity theorem. They apply concepts of triangles to the real world.
Curated OER
Similar Triangles
Young scholars differentiate between similar and congruent triangles. In this geometry lesson, students identify the missing side and angle of a triangle. They identify the different ratio and proportion of the sides of a triangle.
Virginia Department of Education
Similar Figures
How similar do figures have to be to be similar figures? Individuals learn to identify similar figures by verifying that angles are congruent and sides are proportional. Additionally, they match the corresponding parts of similar figures.
EngageNY
The Side-Angle-Side (SAS) and Side-Side-Side (SSS) Criteria for Two Triangles to Be Similar
Playing with mathematics can invoke curiosity and excitement. As pupils construct triangles with given criteria, they determine the necessary requirements to support similarity. After determining the criteria, they practice verifying...
101 Questions
Square Partitions
Challenge your classes while developing their problem-solving skills. A square is divided neatly into four equal triangles by its diagonals until one diagonal is moved from a vertex to the midpoint of one side. Now, scholars must devise...
Curated OER
Angles and Similarity
High schoolers identify triangles as similar or congruent. In this geometry lesson, students drag triangles around on the navigator to see the effect of different angles on the shape of the triangle. They discuss angle similarity and...
Curated OER
Similarity and Congruence
Students explore the concept of similarity and congruence. In this similarity and congruence lesson plan, students cut out strips of paper and form a triangle. Students try to prove that their triangles are congruent using the SSS...
Curated OER
Proportional Similarities
Students model the geometric relationship with graphing. For this geometry lesson, students differentiate between parallel, perpendicular, similar and congruent shapes. They use properties of polygons to differentiate their shapes...
Curated OER
Dihedral Figures
Middle and high schoolers perform transformations. In this web based lesson, students explore dihedral figures. They use the web tools to translate, rotate, and reflect figures. Pupils identify lines of symmetry.
Curated OER
Side Splitter Triangles
Students investigate the side splitter theorem. In this geometry lesson plan, students estimate and solve problems dealing with ratios and proportions. They identify angles created by lines that are parallel.
Curated OER
Soda Cans
Students identify and use properties of similar figures. In this geometry lesson, students use proportions of the sides of triangles to solve triangular relationships. They use soda can as their visuals.
Curated OER
Congruence with Robot Gobot
Students identify the properties of solids and polygons. In this geometry lesson, students identify the different measurements of a triangle. They use congruence parts and theorem to prove their answer.
Curated OER
THE MEAN INDEX CARD
Students cut an index card to create three similar right triangles and explore the congruencies and proportions that exist. They investigate the properties of lines and concepts of congruency, similarity, tangency and symmetry of...
Curated OER
Indirect Measurement
Students measure and apply their knowledge of proportion to solve problems. In this geometry activity, students measure using a meter stick, small mirror and measuring tape. They compare and contrast their measurements to objects outside...
Curated OER
Indirect Measurement, Surveying Trigonometry
Learners measure distances using indirect measurements. In this geometry instructional activity, students apply proportion and ratios to measure heights of different objects. They differentiate between direct and indirect measurements.
Curated OER
An Application of Congruence
Students solve triangles using the properties if congruency. For this geometry lesson, students apply congruent and similar figures to solve real world and math problems. They show they are able to follow instructions.
Curated OER
Dream Bedroom Floor Plan
Students build and apply concepts of geometry. In this geometry lesson, students create a building using proportions and scale drawings. They use Cabri technology to create a virtual drawing first.
Mathematics Vision Project
Circles: A Geometric Perspective
Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...