Education Development Center
Proof with Parallelogram Vertices
Geometric figures are perfect to use for proofs. Scholars prove conjectures about whether given points lie on a triangle and about midpoints. They use a provided dialogue among fictional students to frame their responses.
Noyce Foundation
Pizza Crusts
Enough stuffed crust to go around. Pupils calculate the area and perimeter of a variety of pizza shapes, including rectangular and circular. Individuals design rectangular pizzas with a given area to maximize the amount of crust and do...
Curated OER
Classify Triangles
Here is a classifying triangles practice worksheet in which learners sharpen their problem solving skills as they solve six story problems.
Curated OER
Identifying Triangles
Sixth graders identify and define a variety of triangles. In this identification of triangles instructional activity, 6th graders draw examples of each triangle on a whiteboard, then complete a worksheet.
Curated OER
Inscribed Angles
For this inscribed angles worksheet, 10th graders solve 13 various types of problems related to inscribed angles in geometry. First, they identify a circle illustrated and each arc of the circle. They, students find the measure of each...
Curated OER
Triangles
In this triangles worksheet, 10th graders solve 10 different problems that include determining the measurement of various angles. First, they determine the area of a triangle illustrated on the sheet. Then, students use the picture to...
Curated OER
Right Triangle
In this right triangle worksheet, students find the lengths of the sides of a triangle. This one-page worksheet contains 1 problem.
Curated OER
Special Segments in Triangles
In this special segments in triangles worksheet, 10th graders solve 6 various types of problems related to determining types of segments found in triangles. First, they find a segment if the line parallel is a median or an altitude....
Curated OER
Law of Cosines
For this cosine worksheet, students will find the length of the third side of a triangle given the length of the other two side. Students will use the Law of Cosines to find the length of the missing side. Answers will be rounded to 3...
Curated OER
Congruent Triangles
In this congruent triangles worksheet, 10th graders solve and complete 10 different problems that involve various congruent triangles. First, they determine the length of the third side given the other two. Then, students determine the...
Curated OER
The Law of Cosines
For this Law of Cosines worksheet, students are asked to demonstrate the ability to apply the Trigonometric Law of Cosines and the Inverse Law of Cosines to solve for sides and angles of right triangles.
Curated OER
Law of Sines
Pupils identify the ratios of a right triangle. In this calculus lesson, students use the law of sines to solve problems involving non-right triangles. They identify the different parts of a triangle.
Curated OER
Exploration of Trigonometry
Learners explore how changing an angle in a triangle changes the ratio of the sides. They also explore how changing the sides can make changes to an angle in a triangle. Finally, they determine how two different pairs of sides, in the...
Texas Instruments
What's the Trig?
Learners determine the trigonometric relationships within a triangle as they construct a right triangle on the Ti-89. They find the sine, cosine, and tangent of various angles of their triangle construction.
Curated OER
Special Segments in Triangles
Students identify important properties of triangles. In this geometry lesson, students differentiate between medians, bisectors and altitudes in a triangle. They identify the properties of these important segments.
Curated OER
Mixed Right Triangles
In this geometry worksheet, 10th graders use right triangle trigonometry to find the missing angle measure or side length in right triangles. The one page interactive worksheet contains ten questions. Answers and hints are included.
Curated OER
Pythagorean Theorem
Students discover the Pythagorean Theorem. In this discovering the Pythagorean Theorem lesson, students measure the lengths of various triangles to the nearest centimeter. Students record their measurements in a table. ...
Curated OER
Tessellation Trial and Error
In this interactive lesson, students review attributes of equilateral polygons. They are introduced to the concept of a tessellation. Using protractors and pre-cut shapes, students arrange a variety of tiles to create tessellations. They...
Curated OER
Why Does ASA Work?
Your geometry learners explore Angle-Side-Angle congruence in this collaborative task. The sum of the interior angles of all triangles being one hundred eighty degrees, is the key learners will discover as they explain their reasoning...
Alabama Learning Exchange
"I Saw the Sine"
Discover trigonometric ratios that complement each other. Using two videos, the lesson introduces the trigonometric ratios. The class discovers the relationship between the sine and cosine of complementary angles.
Curated OER
Triangle Congruence
In this triangle congruence learning exercise, students review 4 triangle congruence properties and 4 examples. Students are then prompted to complete 15 problems analyzing whether two triangles are congruent and determine by which...
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...
Del Mar College
Formulas for Elementary and Intermediate Algebra
Give your scholars the support they need to work with formulas. A reference page offers definitions and picture examples of perimeter, area, surface area, volume, the Pythagorean theorem, a variety of shapes, and more.
Curated OER
Geometry In Space
How can we identify shapes in the Universe? High schoolers will compare and contrast elliptic and hyperbolic geometry. They will also explore one possible way to measure the curvature of the Universe, namely, by measuring the sum of the...