Curated OER
Properties of the Centers of a Triangle
High schoolers investigate properties of the four centers of a triangle and explore a special property of the circumcenter and orthocenter of a triangle. This lesson requires the use of Cabri, Jr.
Curated OER
Geometric Figures
In this geometric figures worksheet, 10th graders solve and complete 18 different types of problems that include various figures. First, they find the area of the figures shown if consecutive sides are perpendicular. Then, students find...
Curated OER
The Law of Sines
In this law of sines activity, students use the law of sines to find the missing measurement in a triangle. They determine the value of angles and the lengths of triangles. Students compute the area of triangles. This four-page activity...
Curated OER
Geometry Take Home Question
In this triangles, parallelograms, and kites worksheet, students solve 4 short answer problems. Kids find the area of the given triangle. Students construct parallelograms and kites by cutting out and manipulating the given triangles.
Curated OER
Inscribing a Circle in a Triangle
Pupils investigate inscribing a circle in a triangle. They use Cabri Jr. to draw a triangle, locate the incenter, and use the distance from the incenter to a side of the triangle to inscribe a circle. The dynamic nature of the geometry...
Curated OER
Reflecting a Triangle in the Coordinate Plane
Learners explore geometric concepts using technology. They manipulate the TI to find important math topics. This activity requires a TI-84 or higher.
Curated OER
Section 6.1-6.2 Precalculus: Trigonometry
In this trigonometry worksheet, students solve 15 triangle problems. Students use the law of sines and law of cosines to find the missing angles and side lengths of a triangles.
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
Finding the Area of Triangles
Twelfth graders apply the formula for finding the area of a triangle to various problems. They work real life problems for finding the area of a bathroom and the cost of tiling it. They play a game, Triangle Bingo, where they match...
Curated OER
Area Puzzles
In this area puzzle activity, students the area in square units of 3 triangles, then use those areas and line segments to find find the area of a different set of figures.
Curated OER
Triangles with Collinear Circumcenters
Students identify the circumcenter of a triangle. In this geometry lesson, students construct a perpendicular bisector using a straight edge and a compass. They differentiate between triangles and collinear points.
Curated OER
Law of Sines and Cosines
In this sine and cosine instructional activity, students solve given triangles using the law of sines and cosines. They determine the area of triangles. This three-page instructional activity contains 12 multi-step problems.
Curated OER
Isosceles Triangle Investigation
Pupils solve problems with isosceles triangles. In this geometry lesson, students identify and use the properties of triangles to solve their problems. They find the median, altitude, and angles to the triangles.
Mathematics Vision Project
Module 5: Modeling with Geometry
Solids come in many shapes and sizes. Using geometry, scholars create two-dimensional cross-sections of various three-dimensional objects. They develop the lesson further by finding the volume of solids. The module then shifts...
Balanced Assessment
Walkway
Evaluate different aspects of geometry with one task. An assessment activity prompts learners to determine the area of a pathway in the shape of a parallelogram. The Pythagorean Theorem and area formulas for various polygons provide the...
Cord Online
Pyramids and Cones
Young mathematicians find the surface area and volume of a square pyramid and a cone. In what looks like a typical activity out of a textbook, you'll find an activity where learners find an unknown measurement of a pyramid or...
Illustrative Mathematics
Hexagonal Pattern of Beehives
Young geometers and biologists investigate the math of nature in an activity that is just the bee's knees. Participants will study the tessellations of hexagons in a beehive, along with the natural rationale behind the specific shape....
Mathematics Vision Project
Module 7: Modeling with Geometry
Model good modeling practices. Young mathematicians first learn about cross sections and solids of revolution. They then turn their attention to special right triangles and to the Laws of Sine and Cosine.
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...
Mathematics Assessment Project
Discovering the Pythagorean Theorem
Young mathematicians join the ancient order of the Pythagoreans by completing an assessment task that asks them to find the area of tilted squares on dot paper. They then look at patterns in the squares to develop the...
Curated OER
Area of Triangles
In this area worksheet, students calculate the area of 4 triangles, writing answers in rectangles beneath each triangle. A reference web site is given for additional activities.
Curated OER
Bermuda Triangle: Map Activity
In this Bermuda triangle worksheet, students complete a set of 4 questions using a given map of the Bermuda triangle. Answers are included on page 2.
Curated OER
Leveled Problem Solving Areas of Triangles and Trapezoids
In this geometry learning exercise, 6th graders calculate the area of triangles and trapezoids using the given formulas. They use the formulas to find measurements of lines that are part of the triangles and trapezoids.
Curated OER
Area and Perimeter of Triangles
In this area/perimeter worksheet, learners find perimeter and area of 6 given triangles. An answer key is included on page 2.