Curated OER
Altitudes and Orthocenters: Making Connections to the Nine-Point Circle
Students practice various equations for constructing nine-point circles for triangles.
EngageNY
Construct a Nine-Point Circle
There are an infinite number of points on a circle; can you find nine of them? After putting together a nine-point circle, pupils use constructions and their knowledge of triangle segments to determine the center of the circle. Learners...
Illustrative Mathematics
Two Wheels and a Belt
Geometry gets an engineering treatment in an exercise involving a belt wrapped around two wheels of different dimensions. Along with the wheels, this belt problem connects concepts of right triangles, tangent lines, arc length, and...
EngageNY
Curves from Geometry
Take a another look at ellipses. The seventh segment in a series of 23 in a Precalculus module continues to investigate the graph and equation of an ellipse from the previous lesson. Scholars investigate the fact that the sum of...
Curated OER
Geometry in the Real World
Eighth graders complete a unit of lessons on basic geometry concepts. They participate in a variety of activities, culminating in a project that involves publishing a booklet or a poster that presents the major geometry concepts from the...
Curated OER
Segments Formed by Intersectiong Chords, Secants, and Tangents
Learners investigate the properties of segments formed which chords, secants, and tangents, intersect. The dynamic nature of Cabri Jr. allows students to form and verify conjectures regarding segment relationships.
Curated OER
Perpendicular Segments in a Circle
High schoolers explore the concept of circles as they construct a circle using a program such as Cabri Jr. Learners construct a chord and a diameter that are perpendicular, then measure the bisected chord and notice that both sides of...
Curated OER
Basic Compass and Ruler Construction: Line Segment
For this construction worksheet, students utilize a compass and a ruler to reconstruct a line segment and to combine two line segments together in 2 questions.
Curated OER
Angles, Triangles, Quadrilaterals, Circles and Related
Students classify angles. In this angles lesson, students explore the characteristics of angles, triangles, quadrilaterals and circles. They identify polygons and sing a classifying angles song. Students participate in a manipulative...
Curated OER
Standardized Geometry Test Practice
In this angles, lines and figures review worksheet, 10th graders solve and complete 33 standardized multiple choice problems. First, they use the Segment Addition Postulate to solve for a variable given an equation for each line. Then,...
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...
Curated OER
Identify Polygons: Algebra/Geometry Institute
Eighth graders classify geometric figures. In this polygon lesson plan, 8th graders identify given geometric figures. They compare and contrast different polygons. Students name line segments, identify parallel lines, and...
Curated OER
Segment Formulas Homework
In this geometry worksheet, students examine three different diagrams and apply the appropriate formulas to each of the following situations: two chords, a tangent and a secant, and two secants. There are 17 questions to solve for the...
Bytes Arithmetic
Geometry Pad+
Graphing paper, pencil, ruler, protractor, and compass, all get replaced or supplemented with this dynamic geometry application. Here, you can create, move, and scale many different shapes, as well as, explore and change their properties...
Curated OER
Circles
In this geometry learning exercise, 10th graders apply the circle segment theorems to determine the indicated segment length. The one page learning exercise contains twenty problems. Answers are not provided.
EngageNY
Properties of Tangents
You know about the tangent function, but what are tangent lines to a circle? Learners investigate properties of tangents through constructions. They determine that tangents are perpendicular to the radius at the point of tangency, and...
Mathematics Vision Project
Module 5: Modeling with Geometry
Solids come in many shapes and sizes. Using geometry, scholars create two-dimensional cross-sections of various three-dimensional objects. They develop the lesson further by finding the volume of solids. The module then shifts to finding...
Curated OER
Construct, Bisect, Duplicate: Geometry Practice with Compass and Straight Edge
Geometers employ a straight edge and compass to duplicate and bisect segments and angles, construct perpendiculars, parallel lines, figures, and circles with points of concurrency. Ample practice with 65 questions across 8 worksheets. No...
Curated OER
Exploring Harmonic Conjugates
High schoolers investigate harmonic conjugates using Cabri Software or the Ti Calculator to analyze harmonics. They explore different angles measurements as they move their circles around and solve problems.
Curated OER
Geometry: Basic Constructions
In this geometry activity, 10th graders use a straightedge and a compass to construct congruent segments and angles, bisect a segment and an angle, construct perpendicular and parallel lines, construct tangents, circumscribe a circle...
Curated OER
Dividing Line Segments into n Congruent Parts
Students identify lines, and line segments. In this geometry lesson plan, students divide line segments into equal congruent parts. They complete a laboratory activity dealing with lines and segments.
Curated OER
Area of Sector and Segment
For this area of sector and segment worksheet, 10th graders solve and determine the area of 10 different illustrations. First, they determine the area of a shaded sector given the measurements. Then, students determine the area of each...
Curated OER
Quiz: Area of Sector and Segment
In this area of sector and segment worksheet, students find the area of a shaded sector. Given the central angle of a segment and the radius, students identify the area of a sector. This one-page worksheet contains ten problems.
Curated OER
Tangents and Circles
In this tangents and circles worksheet, 10th graders solve 10 different problems that include various tangents and circles. First, they determine in each diagram whether the segments shown are tangents or not. Then, students determine...