Curated OER
Triangle Inequality Theorem
Students use the inequality theorem to solve triangles and their properties. In this geometry lesson, students are given spaghetti of different lengths and asked to create triangles. They conclude the necessary length needed to make a...
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...
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.
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;...
Curated OER
Interior Angles of Regular Polygons
Students investigate the interior angles of a triangle. In this geometry lesson, students create the formula to calculate the angles inside a triangle. They observe the total sum of a triangles angle on the navigator.
Curated OER
Angles of a Triangle
Learners explore the measures of the angles of a triangle in this geometry lesson. They use Cabri Jr. to investigate the sum of the measures of the interior angles of a triangle, and examine the relationships between the interior and...
Curated OER
Polygon Sum Conjecture
In this geometry instructional activity, 10th graders identify the missing angles using the polygons sum conjecture. They measure exterior and interior angles using their angle theorems. There are 63 problems.
Mathed Up!
Angles in Polygons
Show your class that finding angle measures is a regular calculation with a resource that provides 12 problems dealing with the measures of angles in regular polygons. Pupils use formulas for the sum of measures of angles in a polygon to...
Flipped Math
Unit 3 Review: Parallell and Perpendicular Lines
Learners watch a quick review on the Parallel and Perpendicular Lines unit. The pupils work through ten review problems ranging from identifying types of angles formed by parallel lines and transversals to writing equations of parallel...
Curated OER
Measuring Angles in Triangles
For this measuring angles in triangles worksheet, 10th graders solve 12 different measurement problems with angles within triangles. First, they find the value of x in each triangle given the angle measurements. Then, students find the...
Curated OER
Exterior and Interior Angles of Triangles
Tenth graders explore the exterior and interior angles of triangles. They use a theorem in order to prove a theorem about all polygons. Students use the theorem and its applications to find the angles of different types of triangles.
Improving Measurement and Geometry in Elementary Schools
The Sum of the Interior Angles of a Polygon
Junior geometers discover that polygons can be decomposed into triangles and that the number of triangles can be determined by a rule. Note that the Geometer’s Sketchpad® software is required to carry out all components of this lesson.
Illustrative Mathematics
Find the Missing Angle
This one activity requires young geometers to pull together information they are currently learning with things they have learned previously. Here they rely on understanding something about parallel lines, alternative interior angles,...
Curated OER
Sum of Interior/Exterior Angles with Wilbur
Students identify the interior and exterior measures of polygons. In this geometry lesson, students identify the formula for interior angles of polygons. They differentiate between triangular and polygons angles.
Curated OER
Interior and Exterior Angles of Polygons
Young scholars identify interior and exterior angles of polygons. In this geometry lesson, students add interior and exterior angles of polygons. They use angle theorems to solve the problems.
Curated OER
Patterns in the Sums of Polygon Angles
Sixth graders discover the patterns of sums of polygon angles. In this math lesson, 6th graders study the properties of geometric shapes to solve problems as they participate in hands-on activities.
Curated OER
Polygon Sum Conjecture
Students calculate the sum of the angles of a polygon. For this geometry lesson, students use the interior angle formula of polygon based on the number of sides of the polygon. They identify the missing angle using algebra.
Curated OER
Shapes and Designs
In this shapes and designs worksheet, 10th graders solve and complete 6 different types of problems. First, they fill in the first two columns of the table show with their shapes. Then, students measure the interior angles of each...
Curated OER
Angles in Polygons
In this angles in polygons activity, students determine the value of a missing angle measure. They find the value of interior angles and exterior angles. Polygons include triangles, quadrilaterals, pentagons, and hexagons. This...
Curated OER
Geometric Figure Quiz
In this geometric figure learning exercise, students answer 10 multiple choice questions about geometric figures. Students find missing angles, interior angles, properties of polygons, etc.
Curated OER
Interior/Exterior Polygon Angles and Tessellations
Students discover the sum of the interior and exterior angles of several polygons. In this Geometers sketchpad lesson plan, students work in groups to find the stated measurements of triangles, quadrilaterals, pentagons and hexagons....
Curated OER
Polygons Homework
In this polygons worksheet, students identify polygons that contain given parameters. They write definitions of polygons. Students find the measurement of exterior and interior angles of regular polygons. This two-page worksheet...
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...
Willow Tree
Common Geometric Figures
Geometry could be called the study of figures. An overview of the figures found in a typical geometry course contains a study of different triangles, quadrilaterals, and regular polygons.