Curated OER
Identify Triangles
In thins triangles review learning exercise, students examine 3 triangles and their measurements. Students classify them as acute, right, obtuse, equilateral, isosceles, or scalene.
Curated OER
Triangles
In this triangles activity, students identify 3 triangles by the length of their sides and 3 triangles according to their internal angles.
Curated OER
Math Leagues Contest 1
In this basic algebra worksheet, 8th graders solve and complete 6 different types of algebra problems as described in each box. First, they determine the value of a set of numbers with one pair of positive integers. Then, students...
Curated OER
Algebraic Equations
In this algebraic equations activity, students solve 9 different problems that include various types of equations used on the sheet. First, they determine the solution of a given inequality. Then, students write the greatest common...
Curated OER
Special Right Triangles
In this special right triangles worksheet, 10th graders solve 9 different problems related to measuring various types of right triangles. First, they find the values of x and y in each right triangle shown. Then, students find the length...
Curated OER
Geometry of Triangles - Week 6
In this geometry of triangles worksheet, students find the length of sides, are, and angle measurement of inscribed triangles, pentagons, and midpoint of a line. This two-page worksheet contains seven problems.
Curated OER
Euclidean Geometry
In this Euclidean geometry activity, learners use a straight edge and a compass to create constructions that are possible with Euclid's Postulates. This one-page activity contains two construction problems.
Curated OER
Constructions of Isosceles and Equilateral Triangles
Learners explore the difference between drawing and constructing a triangle utilizing The Geometer's Sketchpad on the computer. They create, develop and script constructions for both isosceles and equilateral triangles. Each student has...
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
Cabri Jr. - Getting Started with Triangles
Young scholars explore a basic triangle construction. In this beginning geometry lesson, students investigate the steps to necessary to create an equilateral triangle with Cabri Jr.;
Curated OER
Equilateral Triangles
In this equilateral triangles worksheet, students study the various triangles to identify equilateral triangles. Students may count the triangles.
Curated OER
Modeling Permutation Group
Students explore the concept of transformations. In this transformations lesson plan, students construct an equilateral triangle and a square with a circumscribed circle. Students reflect and rotate their constructions.
Curated OER
Expressions and Operations
In this expressions and operations learning exercise, 9th graders solve and complete 3 different multiple choice problems. First, they determine the value that is closest to x for the given expression. Then, students find the height of...
Curated OER
Expressions and Operations
In this expressions and operations worksheet, 9th graders solve and complete 3 different problems that include identifying and applying various operations. First, they determine the value closest to the given expression. Then, students...
National Council of Teachers of Mathematics
The Math Forum: Triangle Formulas
Investigate the geometric definitions of triangles, focusing upon equilateral, isosceles, right, and scalene with detailed drawings and appropriate formulas for each. This site has links to more information on triangles.
Texas Instruments
Texas Instruments: Isosceles Triangle
In this activity, students construct isosceles and equilateral triangles. They discover that if two sides of a triangle are congruent, then the angles opposite them are congruent. They understand that an equilateral triangle is also...
Cut the Knot
Cut the Knot!: Napoleon's Theorem
Site that describes in detail Napoleon's theorem. To understand this site be sure you understand what the centroid of an object is. The site describes polygons in terms of the roots of unity of a function. The page gives an interactive...
CK-12 Foundation
Ck 12: Geometry: Equilateral Triangles
[Free Registration/Login may be required to access all resource tools.] In this lesson students apply the properties of equilateral triangles. Students examine guided notes, review guided practice, watch instructional videos and attempt...
CK-12 Foundation
Ck 12: Geometry: Equilateral Triangles
[Free Registration/Login may be required to access all resource tools.] This concept will teach students the properties of equilateral triangles and how to apply them to solve problems. Students examine guided notes, review guided...
University of Cambridge
University of Cambridge: Nrich: Triangles to Tetrahedra
Given an unlimited number of a specific type of equilateral, isosceles, and right triangles create as many tetrahedra as are possible. Includes printout.
Wolfram Research
Wolfram Math World: Equilateral Triangle
MathWorld goes into detail about equilateral triangles at this site. Use this site to find out how to construct an equilateral triangle using a compass and straight edge. Learn about the altitude of such triangles, and the rationality of...
University of California
University of California: Triangles and Simplices
This site from the University of California deals with different applications and topics pertaining to triangles, particularly triangulation.
Illustrative Mathematics
Illustrative Mathematics: G Co, G Srt Seven Circles I
In this task, seven pennies are placed in a circle so that they are all touching one in the center and their neighbors. The question is whether this will work with other equally-sized circles. Aligns with G-SRT.C and G-CO.C.10.
Alabama Learning Exchange
Alex: A Triangle to Remember
This lesson will introduce students to different types of triangles by using a clip from the movie A Walk to Remember. They will take part in interactive tutorials to strengthen the concepts of classifying triangles. The students will...