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
Intersecting Lines and Vertical Angles
Pupils identify and define intersecting lines and vertical angles. They draw two intersecting lines and measure one pair of vertical angles. Learners will also move a line to change the angles of a figure and describe the changes in the...
Curated OER
Investigating the Slopes of Parallel and Perpendicular Lines
High schoolers investigate parallel and perpendicular lines. They use Cabri Jr. to construct and explore the relationships between the slopes of parallel and perpendicular lines. The drawing and measurement tools available with Cabri Jr....
Curated OER
Creating Parallel Lines and Transversals
Have your class create parallel lines. High schoolers will learn how to identify the different angles created by a parallel line cut by a transversal. Then, they identify and name similar and different angles.
Curated OER
Circles and Angles
Students identify tangents, chords and secants. In this geometry instructional activity, students graph circles and identify angles created by secant lines, tangent lines and chords.
Texas Instruments
Copying an Angle
High schoolers will investigate geometric construction in this geometry lesson. Your pupils can explore the basic construction of copying an angle, using the constructions tools of Cabri Jr.
Curated OER
Investigating Equations of Lines
High schoolers investigate linear equations as they use technology (Cabri, Jr.) to explore the equations of lines in slope-intercept form. The technology allows learners to manipulate the line and observe the changes in the parameters of...
Curated OER
Making Parallel Lines
Students differentiate between parallel and perpendicular lines. In this geometry lesson, students make conjectures and apply it to solve real life situations. They collect data and make predictions based on the data.
Curated OER
Geometry: Lesson 8
Eighth graders engage in a lesson that is concerned with the finding of angles that are found in different two dimensional figures. They compare and contrast exterior and interior angles while also determining the unknown measures of...
Curated OER
Naming Angles
In this naming angles worksheet, 10th graders solve 12 different problems by responding to each statement defining the angles shown in each box. They name a linear pair in 3 of the problems and name a pair of supplementary angles in 4...
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
Exploring Angle/Pair Relationships
Students find missing angles and sides of triangles. In this geometry lesson, students create intersecting lines to measure angles. They use Cabri Software to create virtual angles.
Curated OER
Angles, Lines and Transversals
Students identify and determine angle pair relationships. In this geometry lesson, students identify different angles of parallel lines that are cut by transversals. They identify interior and exterior angles after watching a video.
Curated OER
Angle Relationships
In this angle relationships worksheet, 10th graders solve 7 problems related to the different types of angles that occur in pairs. First, they identify each pair of angles as adjacent, vertical, complementary, supplementary, and/or as a...
Curated OER
Inscribed Angles
Students calculate the inscribed angle of a triangle. In this geometry lesson, students identify the angle created by intersection of a triangle and a circle. They see the relationship between the arc and the angle.
Curated OER
Identifying Lines of Symmetry
Students calculate the lines of symmetry using polygons. In this geometry instructional activity, students graph, compare and estimate using collected data. They identify different attributes to the polygons based on their sides.
Mathed Up!
Bearings
Keep the math straight and true. Using information learned about angle relationships, pupils determine drawn bearings, or draw a line with a given bearing. The accompanying video provides the definition of a bearing and its three...
Curated OER
Proportional Segments Between Parallel Lines
High schoolers 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...
EngageNY
Special Lines in Triangles (part 1)
Allow your pupils to become the mathematicians! Individuals explore the properties of a midsegment of a triangle through construction and measurement. Once they figure out the properties, learners use them to draw conclusions.
Charleston School District
Pre-Test Unit 2: Similar and Congruent
A pre-test contains questions about transformations that lead to congruent and similar images. It also covers angle relationships associated with triangles and parallel lines intersected by a transversal.
Curated OER
Exploring Angle Pair Relationships
Young scholars investigate the relationship between angles of triangles. In this geometry lesson, students identify properties of right and non-right triangles. They differentiate between vertical and supplementary angles.
Curated OER
Concurrent Lines in Triangles
Students explore the concept of concurrent lines in triangles. In this concurrent lines in triangles lesson, students work in groups to investigate properties of concurrent lines in acute, right, and obtuse triangles. Students use a...
Curated OER
Angle Pairs
Students identify different angle pairs. In this geometry lesson, students identify the different angles of two parallel lines cut by a transversal. They identify the interior and exterior angles.
Curated OER
Geometric Proof and Angles
In this geometry activity, 10th graders write two-column and paragraph proofs to prove angle pair relationships. The one page activity contains five problems. Answers are not included.