Curated OER
Similar Polygons
In this similar polygons worksheet, 10th graders solve 10 different problems that include determining various similar polygons. First, they determine the perimeter of a second triangle given the measures of all angles in the first. Then,...
Curated OER
Transformations in the Coordinate Plane
Your learners connect the new concepts of transformations in the coordinate plane to their previous knowledge using the solid vocabulary development in this unit. Like a foreign language, mathematics has its own set of vocabulary terms...
EngageNY
The Angle-Angle (AA) Criterion for Two Triangles to Be Similar
What do you need to prove triangles are similar? Learners answer this question through a construction exploration. Once they establish the criteria, they use the congruence and proportionality properties of similar objects to find...
Curated OER
Tile Patterns I: Octagons and Squares
This can be used as a critical thinking exercise in congruence or as a teaching tool when first introducing the concept. Four octagons are arranged in such a way that a square is formed in the middle. With this information, geometry...
Curated OER
Similar Figures
In this similar figures learning exercise, students identify corresponding sides and corresponding angles of given polygons. They identify similar figures. This three-page learning exercise contains 18 problems.
Houghton Mifflin Harcourt
Unit 5 Math Vocabulary Cards (Grade 6)
Acute angle, line of symmetry, and vertex are a few terms you'll find in a set of 90 flashcards designed to reinforce math vocabulary. Included in the set are two types of cards; a word card printed in bold font, and a definition card...
EngageNY
Properties of Parallelograms
Everyone knows that opposite sides of a parallelogram are congruent, but can you prove it? Challenge pupils to use triangle congruence to prove properties of quadrilaterals. Learners complete formal two-column proofs before moving on to...
Virginia Department of Education
How Many Triangles?
Something for young mathematicians to remember: the sum of any two sides must be greater than the third. Class members investigates the Triangle Inequality Theorem to find the relationship between the sides of a triangle. At the same...
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
Corresponding Parts of Similar Triangles
Here is a lesson that has learners take a look at corresponding parts of similar triangles, ratios of similarity, reductions and enlargements. They'll manipulate the scale factor (r) to observe the changes in similar triangles and then...
Curated OER
Exploring Characteristics Needed to Prove Two Trianlges Congruent
Tenth graders explore congruent triangles. In this geometry lesson, 10th graders investigate the conditions necessary to prove two triangles congruent. The lesson combines dry erase board activities and the use of technology.
Curated OER
Measurement of Angles
Young scholars measure angles that are formed by parallel lines and a transversal lines. In this angles lesson plan, students measure and define angles that are made by parallel and transversal lines. They will color code the angles...
Curated OER
Measurement of a Central Angle
Students calculate the measurement of a central angle. In this geometry lesson, students identify properties of circles. They use Cabri software to create and analyze graphs.
Curated OER
Searching for Angles and Lines
Students work to find and reinforce concepts related to lines and angles. They identify the characteristics of shapes that have one, two, and three dimensions. The students also work on definitions related to the geometry of shapes.
Inside Mathematics
Rhombuses
Just what does it take to show two rhombuses are similar? The assessment task asks pupils to develop an argument to show that given quadrilaterals are rhombuses. Class members also use their knowledge of similar triangles to show two...
Concord Consortium
Isosceles Triangle Spaces
How many different types of triangles can your class name? A discovery lesson guides learners through an exploration of the different triangle types and the relationships between their angles and sides. Using coordinate geometry,...
Curated OER
Proportional Segments Between Parallel Lines
Learners identify similar triangles. In this proportional segments lesson, students identify corresponding sides, set up ratios, and find the length of the missing side of a triangle. They use the parallel/proportionality conjecture to...
Curated OER
Exploring Similar Polygons
In this exploring similar polygons worksheet, 10th graders solve 9 various types of problems related to determining whether each polygon is similar or not. First, they write 3 equal ratios to show corresponding sides are proportional to...
Illustrative Mathematics
Midpoints of the Sides of a Paralellogram
This task asks learners to prove that the segment joining the midpoints of two sides of a parallelogram is both congruent and parallel to an adjacent side of the parallelogram. The activity would be good to use in a discussion about how...
Curated OER
Indirect Measurement with Similar Triangles
Young scholars use similar triangles to find missing heights. In this using similar triangles to find missing heights lesson, students use proportions to find the heights of missing side lengths. Young scholars find the height of trees...
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.
Inside Mathematics
Hopewell Geometry
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
Curated OER
Identifying Similar Triangles
In this identifying similar triangles worksheet, 10th graders solve 6 different types of problem that include identifying and comparing similar triangles. First, they identify the three ways that determine whether two triangles are...
Curated OER
Exploring Similar Polygons
In this exploring similar polygons worksheet, 10th graders solve 9 various problems that are related to similar polygons. First, they define similar and the symbol used to identify similar to another. Then, students find the measurement...