EngageNY
Looking More Carefully at Parallel Lines
Can you prove it? Making assumptions in geometry is commonplace. This resource requires mathematicians to prove the parallel line postulate through constructions. Learners construct parallel lines with a 180-degree rotation and then...
Mathematics Vision Project
Module 3: Geometric Figures
It's just not enough to know that something is true. Part of a MVP Geometry unit teaches young mathematicians how to write flow proofs and two-column proofs for conjectures involving lines, angles, and triangles.
EngageNY
Solve for Unknown Angles—Angles in a Triangle
Assist your class with each angle of geometry as they use exterior angles to form linear pairs with adjacent interior angles. They cover multiple vocabulary terms and work practice problems, complete with justifications, before taking an...
EngageNY
Segments That Meet at Right Angles
Can segments be considered perpendicular if they don't intersect? Learners look at nonintersecting segments on the coordinate plane and make conclusions about the lines that contain those segments. They determine if they are...
EngageNY
How Do Dilations Map Angles?
The key to understanding is making connections. Scholars explore angle dilations using properties of parallel lines. At completion, pupils prove that angles of a dilation preserve their original measure.
Curated OER
City Streets: A Fold-up of a Street Lined with Buildings
After walking in a nearby neighborhood, have your class create this amazing city street pop-up. They study the facades of the buildings they see, focusing on geometric line, shape, and architecture. They then draw, cut, and create a city...
Curated OER
Sample Lesson Plan on Lines and Angles
Student complete worksheet using the definitions of lines and angle vocabulary. They define the word and follow a direction given on the worksheet such "construct a line." They complete an online tutorial on how to measure angles using a...
Curated OER
Interactivate - Lines, Rays, Line Segments, and Planes
Students explore lines, rays, line segments, and planes. In this math lesson, students discuss the math concepts and direct their instructor in graphing functions. Students collaborate in graphing additional functions.
Alabama Learning Exchange
Origami Geometry
Origami is an excellent way to combine Japanese culture, art, and geometric shapes into one engaging instructional activity! Scholars begin by listening to the story Sadako and the Thousand Paper Cranes and learn the origin of the...
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
Points, Lines, and Line Segments - Homework 16.1
In this geometry worksheet, students complete a homework assignment in which they name 3 lines and line segments. They write parallel, intersecting, or perpendicular, to describe the relationships between 4 pairs of lines. They draw an...
EngageNY
Secant Lines; Secant Lines That Meet Inside a Circle
Young mathematicians identify different cases of intersecting secant lines. They then investigate the case where secant lines meet inside a circle.
Curated OER
Geometry, Lines and Angles
In this lines and angles worksheet, students answer 10 multiple choice questions about lines and angles.
Curated OER
Geometry Worksheet: Angle (4)
In this geometry angle activity, students examine find the measurement of given angles. This one-page activity contains two problems.
CK-12 Foundation
Vertical Angles
Examine vertical angles from a different angle. Moving one line in an intersecting pair of lines lets users see relationships between vertical angles. They finish by answering some machine-scored questions on the topic.
CK-12 Foundation
Linear Pairs: Angles and Lines in a Perspective Drawing
Gain some perspective on linear pairs. Aspiring mathematicians adjust the vanishing point on a perspective drawing. They see the effect on linear pairs of angles and answer five challenge questions based on their observations.
CK-12 Foundation
Bisectors of Line Segments and Angles: Cut an Angle
Explore constructions through an interactive online lesson. Given an example of an angle bisector construction, learners investigate the markings to determine the method used. Challenge questions help solidify the steps.
Curated OER
Tell Me! Geometry
In this geometry and measurement activity, students solve 20 problems pertaining to parallel lines, geometric figures, right angles and simple measurements.
Curated OER
Interactivate - Geometry in Tessellations
Students use an on-line worksheet to experiment with patterns of tessellations in regular polygons. As students observe different shapes in the "Tessellate" Activity they complete a data table and practice making predictions for...
Lone Star College
Geometry Worksheet II
Young geometers get practice with the algebra of angles in an extensive skills practice worksheet. Supplementary, complementary, and vertical angle relationships are used, along with parallel lines cut by a transversal and angle sum of a...
Radford University
Parallel Lines, Transversals, and Angles: What’s the Connection?
Streets, bridges, and intersections, oh my! Parallel lines and transversals are a present in the world around us. Learners begin by discovering the relationship of the angles formed by parallel lines and a transversal. They then apply...
Geometry Accelerated
Accelerated Geometry Review Sheet
Your geometry learners use their knowledge of various geometric concepts to write proofs. Starting with givens containing parallel line segments with transversals and triangles and quadrilaterals, and the mid-point and distance formulas;...
EngageNY
Angle Sum of a Triangle
Prove the Angle Sum Theorem of a triangle using parallel line and transversal angle relationships. Pupils create a triangle from parallel lines and transversals. They find angle measures to show that the angles of a triangle must total...
Mt. San Antonio Collage
Isosceles Triangles and Special Line Segments
Under which conditions can a triangle be classified as isosceles? High schoolers practice identifying isosceles triangles and special line segments, including angle bisectors, medians of triangles, and perpendicular bisectors of sides of...