EngageNY
Proving the Area of a Disk
Using a similar process from the first lesson in the series of finding area approximations, a measurement resource develops the proof of the area of a circle. The problem set contains a derivation of the proof of the circumference formula.
EngageNY
How Do Dilations Map Segments?
Do you view proofs as an essential geometric skill? The resource builds on an understanding of dilations by proving the Dilation Theorem of Segments. Pupils learn to question and verify rather than make assumptions.
Illustrative Mathematics
Equal Area Triangles on the Same Base II
A deceptively simple question setup leads to a number of attack methods and a surprisingly sophisticated solution set in this open-ended problem. Young geometers of different strengths can go about defining the solutions graphically,...
Curated OER
Getting It Right! An Investigation of the Pythagorean Theorem
Learners construct a variety of right triangles using a right-angled set square, cutting corners from pieces of paper or cardboard, and using dynamic geometry software. They measure the sides of these various right triangles and record...
Curated OER
Angle Bisectors
In this angle bisector worksheet, 10th graders solve and complete 23 various types of geometry problems. First, they find the angles listed in the figure shown. Then, students determine the sum of the interior angles of a polygon. They...
Curated OER
The Truth About Triangles And Proofs
Students engage in a lesson plan that is about the classification of triangles and the mathematical proofs involved in working with them. They work on a variety of problems that are created by the teacher with the focus upon the...
Curated OER
Word Problem Practice Workbook
Need worksheets that challenge your middle schoolers to apply their understanding of math? Problem solved! From integers, fractions, and percents, to algebra, geometry, and probability, over 100 pages of word problem worksheets are...
Curated OER
Angles in Polygons
In this geometry instructional activity, 10th graders solve problems involving quadrilaterals using the angle sum of quadrilaterals. They solve for linear pairs, opposite angle theorem and triangular angles. There are 5 questions.
Old Dominion University
Introduction to Calculus
This heady calculus text covers the subjects of differential and integral calculus with rigorous detail, culminating in a chapter of physics and engineering applications. A particular emphasis on classic proof meshes with modern graphs,...
Curated OER
Identify the Shape
10 this geometry worksheet, students identify the different angles created by polygons and name the shape created based on the number of sides. There is an answer key.
Shodor Education Foundation
Cross Sections
Use this activity on cross-sections of three-dimensional shapes in your math class to work on algebra or geometry Common Core standards. The lesson includes a list of relevent terminology, and a step-by-step process to illustrate the...
Curated OER
Pythagorean Theorem by Graphic Manipulation
There are many different ways to show a proof of the Pythagorean Theorem. Here is a nice hands-on paper cutting activity that shows a graphic representation. You can even challenge your young Pythagoreans to come up with their own...
Curated OER
Investigating Area Using Tangrams
Tenth graders connect the history of geometry to problem solving. In this geometry lesson, 10th graders investigate polygons through hands on manipulatives and solve problems relating to parallelograms and triangles. They calculate the...
Curated OER
Regular Polyhedra
Tenth graders investigate the history of geometry and its different shapes. In this geometry lesson, 10th graders practice seeing three dimensional shapes and explain why there are only five polyhedra. They relate all the new materials...
Curated OER
Parallel and Perpendicular Lines
Tenth graders explore parallel and perpendicular lines. In this geometry lesson, 10th graders investigate the relationships associated with parallel lines and transversals, perpendicular lines, and the angles formed by these lines. ...
Virginia Department of Education
Circles in the Coordinate Plane
Make the connection between the distance formula and the equation of a circle. The teacher presents a lesson on how to use the distance formula to derive the equation of the circle. Pupils transform circles on the coordinate plane and...
Curated OER
Logical Relationship of Postulates & Theorems
In this postulates and theorems worksheet, students explore a concept map containing information about angles and sides, alternate interior angles, and diagonals of a parallelogram. They use the concept map to prove theorems dealing...
Curated OER
Picking Pythagoras
Learners discover that side measurement is used in determining angle classification of a triangle. By squaring sides, they predict whether triangles be right, obtuse, or acute. They prove the Pythagorean Theorem and use it to solve...