EngageNY
Congruence, Proof, and Constructions
This amazingly extensive unit covers a wealth of geometric ground, ranging from constructions to angle properties, triangle theorems, rigid transformations, and fundamentals of formal proofs. Each of the almost-forty lessons...
Curated OER
Connecting Algebra and Geometry Through Coordinates
This unit on connecting algebra and geometry covers a number of topics including worksheets on the distance formula, finding the perimeter and area of polynomials, the slope formula, parallel and perpendicular lines, parallelograms,...
Mathematics Vision Project
Geometric Figures
Logical thinking is at the forefront of this jam-packed lesson, with young mathematicians not only investigating geometric concepts but also how they "know what they know". Through each activity and worksheet, learners wrestle with...
Mathematics Vision Project
Module 6: Congruence, Construction, and Proof
Trace the links between a variety of math concepts in this far-reaching unit. Ideas that seem very different on the outset (like the distance formula and rigid transformations) come together in very natural and logical ways. This...
Mathematics Vision Project
Module 2: Congruence, Construction and Proof
Construct yourself a winning geometry unit. A set of lessons introduces geometry scholars to constructions and proofs with compasses and straightedges. It also covers triangle congruence through transformations. This is the second of...
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...
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.
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...
Arizona Department of Education
Area and Perimeter of Regular and Irregular Polygons
Extend young mathematicians' understanding of area with a geometry lesson on trapezoids. Building on their prior knowledge of rectangles and triangles, students learn how to calculate the area of trapezoids and other...
Cuemath
Cuemath: Angle Bisector Theorem
This short lesson focuses more on the angle bisector theorem. Learn about the angle bisector theorem proof, triangle angle bisector theorem, how to construct angle bisector, and other interesting properties and facts around angle bisectors.
CK-12 Foundation
Ck 12: Geometry: Two Column Proofs Intermediate
[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to write two-column proofs, and provides proofs for the Right Angle Theorem, Same Angle Supplements Theorem, and Vertical Angles...
Khan Academy
Khan Academy: Inscribed Angle Theorem Proof
Proving that an inscribed angle is half of a central angle that subtends the same arc.