Curated OER
Formula Determination
Students derive a formula for the interior degrees in any convex polygon. For this geometric figure lesson, students determine the shapes of various polygons and the number of triangles formed. They use this information to derive the...
Curated OER
The Pythagorean Theorem, the Distance Formula, and Slope
Students explore the concept of the Pythagorean Theorem. For this Pythagorean Theorem lesson, students derive the distance formula and slope of a line from the Pythagorean Theorem.
Curated OER
CORNER CABINET
Ninth and tenth graders calculate the length, width, height, perimeter, area, volume, surface area, angle measures or sums of angle measures of common geometric figures. They solve problems involving scale drawings, models, maps or...
Curated OER
Connecting Formulas Related to Geometric Figures
Young scholars identify diagrams of quadrilaterals and circles by different names and classify the figures. They name the areas for each diagram and practice solving the formulas for each.
Curated OER
Angle Sum and Difference
In this angle sum and difference activity, 11th graders solve 10 different problems related to determining the angle sum and difference of numbers. First, they determine the exact value of sine and cosine degrees. Then, students utilize...
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
Triangle Exterior Angles Theorem
Students identify the measure of missing exterior angles. For this geometry lesson,students define and apply the exterior angle theorem to solve problems. They use Cabri software to create different angles and make investigations.
Curated OER
Triangles
In this triangles worksheet, 10th graders solve 12 different problems that include various angles of triangles. First, they determine the measure of an exterior angle. Then, students determine the measure of any of the base angles of an...
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
Cyclic Quadrilaterals
What does it mean for a quadrilateral to be cyclic? Mathematicians first learn what it means for a quadrilateral to be cyclic. They then investigate angle measures and area in such a quadrilateral.
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.
EngageNY
Similar Triangles in Circle-Secant (or Circle-Secant-Tangent) Diagrams
First angle measures, now segment lengths. High schoolers first measure segments formed by secants that intersect interior to a circle, secants that intersect exterior to a circle, and a secant and a tangent that intersect exterior to a...
Radford University
How Much is in There? A Polygon Investigation
Try to find the triangles in various polygons. An investigation has learners develop a formula for the sum of the measures of the interior angles of a polygon. They use manipulatives to partition each polygon into triangles, then...
Curated OER
Properties and Attributes of Polygons
In this geometry worksheet, 10th graders determine if a polygon is convex or concave and apply the polygon Angle sum theorem and the polygon exterior angle sum theorem to determine the measures of interior and exterior angles of a...
Curated OER
Algebra and Trigonometry - Week 3: Story Problems
In this story problem learning exercise, students read story problems, write equations, and solve. They use the law of sines, the law of cosines, the distance formula, and rates to solve problems. This two-page learning exercise contains...
Curated OER
Math Handbook: Trigonometry
You'll be spinning in unit circles once you read through this jumbo-sized resource of everything you need to know about trigonometry. Each page has color-coded examples with explicit directions that detail the problems and formulas.
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.
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
Trigonometry - Week 9
In this trigonometry worksheet, learners use the sum-to-product formula, and the law of sines and cosines to solve trigonometry problems. This two-page worksheet contains eight problems.
Curated OER
Circles Terminology Multiple Choice
In this circles worksheet, students solve 10 multiple choice problems. Students answer questions about diameter and chord relationships, tangent lines to a circle, circumference, the Pi relationship, etc.
Willow Tree
The Pythagorean Theorem
There isn't a more popular geometry formula than the Pythagorean Theorem! Learners understand the special side relationships in a right triangle. They use the Pythagorean Theorem to find missing sides and to solve problems. They begin...
Curated OER
Solidly Platonic
When they do, they learn. Using this resource, young mathematicians learn about platonic solids by actually building, touching, and examining the shapes. They connect their observations about the shapes to Euler's formula.
Curated OER
A Rectangle in the Coordinate Plane
A quadrilateral is drawn on the coordinate plane, and eighth grade geometers find the length of each side and the diagonals by applying the Pythagorean theorem.
Curated OER
Application of Delta-Epsilon Definition of the Limit
Students create a Hexaflexagon using a formula. In this calculus lesson, students apply the definition of delta epsilon as it relates to limit to create a shape using creases. They relate the same rule to triangles and investigate angles.