El Paso Community College
Geometry Definitions
Geometry is full of shapes, figures, and corresponding things here and there. The guide shares all of the key pieces of geometric information in a nicely color-coded and labeled sheet.
Illustrative Mathematics
Is This a Parallelogram?
If both pairs of opposite sides of a quadrilateral are congruent, is the quadrilateral a parallelogram? This task asks learners to determine the answer and to support their answer with a proof. The resource includes a commentary for...
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
Proving Lines Parallel
In this proving lines parallel learning exercise, 10th graders solve 10 different types of problems that prove that various lines are parallel to each other. First, they find the value of x so that line a is parallel to line b. Then,...
Curated OER
Angles and Parallel Lines
In this angles and parallel lines worksheet, 10th graders solve 12 different types of problems that include measuring various angles and parallel lines in given figures. First, they find the measure of each angle using the figure shown....
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...
Education Development Center
Proof with Parallelogram Vertices
Geometric figures are perfect to use for proofs. Scholars prove conjectures about whether given points lie on a triangle and about midpoints. They use a provided dialogue among fictional students to frame their responses.
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...
Curated OER
Alternate Interior Angles
Label angles of parallel lines to analyze the angles created by a transversal and two parallel lines. They graph their lines and observe the similarity and difference in the angles.
GeoGebra
Conjectures and Proof
Transform proofs using triangle rotations. By rotating a triangle around various points, class members develop proofs. Participants prove relationships of alternative interior angles formed by parallel lines and the sum of the interior...
Curated OER
Angles and Parallel Lines Homework
In this geometry worksheet, students identify the angles formed by parallel lines and a transversal. They differentiate between the angles of a transversal and that of a perpendicular line. There are 14 questions.
Curated OER
Angles and Parallel Lines
In this geometry worksheet, students identify the interior and exterior angles of parallel lines cut by a transversal. There are 11 questions with an answer key.
Curated OER
Angle Action 1,2 and 3
Students investigate angles through construction. In this geometry lesson, students use a protractor to identify the measurement of an angle. They identify angles cut by a transversal and two parallel lines.
Curated OER
Similar Polygons
In this similar polygons worksheet, students identify the corresponding sides of polygons. They use proportions to solve problems. Students determine the scale factor of similar figures. This two-page worksheet contains diagrams and...
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.
Mt. San Antonio Collage
The Trapezoid
Enjoy this nicely organized worksheet that puts together multiple problems regarding trapezoid proofs. The resource can be used as a guide that begins with proving properties and ends with solving for measures of line segments.
Virginia Department of Education
High School Mathematics Geometry Vocabulary Word Wall Cards
Having a good working knowledge of math vocabulary is especially important for geometry learners. Here are 119 pages worth of wonderfully constructed definitions, constructions, formulas, properties, theorems, and postulates. This is a...
EngageNY
Similarity and the Angle Bisector Theorem
Identifying and verifying reproducible patterns in mathematics is an essential skill. Mathematicians identify the relationship of sides when an angle is bisected in a triangle. Once the pupils determine the relationship, they prove it to...
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...
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...
EngageNY
More About Similar Triangles
Determine whether two triangles are similar. The lesson presents opportunities for pupils to find the criterion needed to show that two triangles are similar. Scholars use the definition of similarity to find any missing side...
Curated OER
Points, Lines, Planes, and Space
In this points, lines, planes, and space worksheet, students solve word problems dealing with points, lines, planes, and space. Students complete 20 individual problems and 20 group problems.
Curated OER
Hypatia: Angles
Introduce your young geometers to Hypatia, the first noted Greek female mathematician, and the properties of angles. Though this resource is missing worksheets that are needed to complete the lesson, the structure is sound and learning...
Curated OER
Logical Relationship of Postulates & Theorems
For this postulates and theorems worksheet, students explore a concept map containing information about angles and sides, alternate interior angles, and diagonals of a parallelogram. They use the concept map to prove theorems dealing...