EngageNY
Circles, Chords, Diameters, and Their Relationships
A diameter is the longest chord possible, but that's not the only relationship between chords and diameters! Young geometry pupils construct perpendicular bisectors of chords to develop a conjecture about the relationships between chords...
Curated OER
Geometry Challenge
Students explore angle relationships and measure angles with a protractor by hand and online. They explore various websites and complete online activities and complete a worksheet.
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...
Alabama Learning Exchange
"I Saw the Sine"
Discover trigonometric ratios that complement each other. Using two videos, the lesson introduces the trigonometric ratios. The class discovers the relationship between the sine and cosine of complementary angles.
West Contra Costa Unified School District
Parallel Lines Cut by a Transversal
Parallel lines seem so right for each other. It's too bad they'll never, ever meet. Learners use tracing paper to discover relationships among angles formed by two parallel lines cut by a transversal. They apply this information to find...
EngageNY
End-of-Module Assessment Task: Grade 7 Mathematics Module 6
Determine the level of understanding within your classes using a summative assessment. As the final lesson in a 29-part module, the goal is to assess the topics addressed during the unit. Concepts range from linear angle relationships,...
Willow Tree
Ratios and Proportions with Congruent and Similar Polygons
Investigate how similar and congruent figures compare. Learners understand congruent figures have congruent sides and angles, but similar figures only have congruent angles — their sides are proportional. After learning the...
Bowland
Three of a Kind
One is chance, two is a coincidence, three's a pattern. Scholars must determine similarities and differences of a regular hexagon undergoing dilation. They look at lengths, angles, areas, and symmetry.
EngageNY
End-of-Module Assessment Task - Grade 8 Mathematics (Module 2)
Can your classes apply the knowledge they have learned? Use this performance task to find out! Individuals use transformations to explain congruence and angle relationships within parallel lines to find missing values. They show what...
Curated OER
Geometric Angles
Learners explore angles and their use in Geometry. Students investigate three different kinds of angles: obtuse, acute, and right angles through an online activity. They identify pairs of angles with special relationships: vertical,...
Curated OER
Linear Pair Worksheet
For this linear pair worksheet, students use the linear pair theorem to calculate missing angle measurements. This two-page worksheet contains 6 problems. Answers are provided on the last page.
EngageNY
Prove the Pythagorean Theorem Using Similarity
Amaze your classes with the ability to find side lengths of triangles immediately — they'll all want to know your trick! Learners use the Pythagorean Theorem and special right triangle relationships to find missing side lengths.
Curated OER
Pythagorean Relationships
Oh that Pythagorean Theorem is so useful. Learners engage in a 45 minute learning activity that requires them to solve for missing angles and sides of a right triangle. They'll use the Pythagorean Theorem to find the rations of sides and...
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...
Hotchalk
Triangle Sum Theorem
Your visual geometry learners will appreciate triangle drawings as they model the triangle sum theorem and algebraically solve to find the missing interior angle in a triangle. Practice problems increase in complexity and vary in their...
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.
Curated OER
Angles: Angles, Angles, Everywhere
Students practice estiminating and measuring angles. After watching a short video, they identify angles in objects in the classroom and their homes. In groups, they participate in activities in which they are given a scenerio and are...
Curated OER
Angles and Transversals
Pupils explore the concept of angles and transversals. They construct parallel and non-parallel lines cut by a transversal using Cabri Jr. Learners then determine which angles are congruent and the relationship of angles when two lines...
Curated OER
Measuring Angles in a Quadrilateral
High schoolers explore quadrilaterals in this geometry lesson. They will draw a quadrilateral, measure the angles, and find the sum of the measures of the interior angles using Cabri Jr. The interactive capabilities of Cabri Jr. allow...
Curated OER
Properties of Angles, Lines, and Triangles
In this properties of angles, lines and triangles instructional activity, 10th graders solve and complete 28 different problems that include determining the measurement of various figures shown. First, they use the geometric properties...
Curated OER
Geometry Lines and Angles
In this lines and angles worksheet, 10th graders solve and complete types of problems that include different line segments and angles to identify. First, they determine whether each line is parallel, skew, or perpendicular in the diagram...
EngageNY
Cyclic Quadrilaterals
What does it mean for a quadrilateral to be cyclic? Mathematicians first learn what it means for a quadrilateral to be cyclic. They then investigate angle measures and area in such a quadrilateral.
Curated OER
Classifying Angles
In this classifying angles worksheet, 10th graders solve and complete 35 various types of problems. First, they match each type of angle with its correct description. Then, students determine whether the given lines or planes are...
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.