Everyday Mathematics
Mathematics Within: Slope and Triangles
Learners discover a method for determining the slope of a line by creating and comparing similar triangles. They fold coordinate grids to make three similar triangles then measure the sides to compare the relationships between the...
Curated OER
Congruent and Similar figures
Eighth graders explore congruent and similar figures. In this eighth grade geometry lesson, 8th graders use geoboards to create congruent and similar figures and explore the relationships between the sides and angles.
Inside Mathematics
Quadrilaterals
What figure is formed by connecting the midpoints of the sides of a quadrilateral? The geometry assessment task has class members work through the process of determining the figure inscribed in a quadrilateral. Pupils use geometric...
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...
Curated OER
Atomic Absorption Determination of Zinc and Copper in a Multivitamin
Advanced lab apprentices prepare zinc and copper solutions to which they will compare the same minerals from a multivitamin. Using absorption spectroscopy, they analyze the contents of the multivitamin for concentration. This lab can be...
Illustrative Mathematics
Base and Height
It is easy to find the area of a triangle where the base and the height are given. But in this resource, it is up to your geometers to identify the base and height of the triangle. In fact, your pupils will learn that there are three...
EngageNY
Modeling Using Similarity
How do you find the lengths of items that cannot be directly measured? The 13th installment in a series of 16 has pupils use the similarity content learned in an earlier resource to solve real-world problems. Class members determine...
Curated OER
Angular Size and Similar Triangles
In this angular size and similar triangles activity, students use the properties of similar triangles and the ratios of sides to solve for unknowns in given diagrams.
Curated OER
Identifying Similar Triangles
In this identifying similar triangles activity, 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 instructional activity, 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...
Curated OER
Arc Measurement Based on The Measurement of a Central Angle
Students define keywords that are important to solve problems. In this geometry instructional activity, students find the arc length and angle of a circle. They convert between radians and degrees.
Curated OER
Similarity
Students find the factor of proportionality in similar polygons. For this similarity of polygons lesson plan, students measure the sides and angles of polygons and derive a factor of proportionality between corresponding pairs of sides...
Curated OER
Measurement of Angles
Students 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 based on...
EngageNY
Similarity
Learn similarity through a transformations lens! Individuals examine the effects of transformations and analyze the properties of similarity, and conclude that any image that can be created through transformations is similar. The...
Curated OER
Parallel Lines and Types of Angles
In this angles and parallel lines worksheet, students solve 40 problems that pertain to parallel lines, supplementary, vertical, corresponding and alternate angles. There is instruction on the page with examples. This page is intended as...
Curated OER
Measurement of a Central Angle
Learners 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.
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...
Houghton Mifflin Harcourt
Unit 7 Math Vocabulary Cards (Grade 6)
Thirty-eight flashcards make up a set designed to reinforce math vocabulary. Two types of cards can be found here; a word card in bold lettering, and a corresponding definition card that offers a labeled example. Terms include area,...
Curated OER
Proportional Segments Between Parallel Lines
Students identify similar triangles. In this proportional segments instructional activity, students identify corresponding sides, set up ratios, and find the length of the missing side of a triangle. They use the...
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...
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.
Willow Tree
The Pythagorean Theorem
There isn't a more popular geometry formula than the Pythagorean Theorem! Learners understand the special side relationships in a right triangle. They use the Pythagorean Theorem to find missing sides and to solve problems. They begin...
Curated OER
The Truth About Triangles And Proofs
High schoolers engage in a lesson that is about the classification of triangles and the mathematical proofs involved in working with them. They work on a variety of problems that are created by the teacher with the focus upon the...
Curated OER
Indirect Measurement with Similar Triangles
Students use similar triangles to find missing heights. In this using similar triangles to find missing heights instructional activity, students use proportions to find the heights of missing side lengths. Students find the...