Curated OER
Classifying Triangles Using Sides
In this geometry activity, students answer 8 fill in the blank questions where they must examine 5 different complex geometric figures to classify triangles.
101 Questions
Best Triangle
What makes an equilateral triangle equilateral? It turns out it's much more than just the side lengths! Learners analyze four different triangles to determine the best equilateral triangle. They create a formula that they later use to...
Curated OER
Triangles
In this math worksheet, students answer 3 questions about an equilateral triangle. Students then answer 3 questions about isosceles triangles. Students then calculate missing angles on isosceles triangles.
K12 Reader
Classifying Triangles
Bring math and reading informational text together with a reading comprehension lesson. After kids read about isosceles, scalene, and equilateral triangles, they answer five comprehension questions to demonstrate how they can use context...
Curated OER
Circles: Geometry Review Worksheet
Tenth graders solve and complete 14 different geometry problems. First, they find the area and circumference of a circle with a given radius. Then, they find the area between a circle and an inscribed equilateral triangle given the...
McGraw Hill
Triangles
After reviewing characteristics of seven types of triangles, young geometers discover how to find the missing angle of a triangle. Then, they practice identifying triangles, find missing angles, and find missing side lengths of similar...
EngageNY
Construct an Equilateral Triangle (part 2)
Triangles, triangles, and more triangles! In this second installment of a 36-part series, your young mathematicians explore two increasingly challenging constructions, requiring them to develop a way to construct three triangles that...
Noyce Foundation
Lyle's Triangles
Try five problems on triangles. Levels A and B focus on shapes that can be created from right triangles. Level C touches upon the relationship between the area of a six-pointed star and the area of each triangle of which it is composed....
Curated OER
Right Triangles
In this right triangles worksheet, 10th graders solve and complete 13 different problems. First, they find the lengths of both missing sides. Then, students find the altitude of an equilateral triangle given the measure of one side. They...
Virginia Department of Education
How Many Triangles?
Something for young mathematicians to remember: the sum of any two sides must be greater than the third. Class members investigates the Triangle Inequality Theorem to find the relationship between the sides of a triangle. At the same...
Curated OER
Equilateral Triangles
Students examine the attribute of equilateral triangles. In this equilateral triangle lesson, students examine a number of paper triangles to determine how they are classified. They determine how triangles are depicted in Navajo rugs.
Curated OER
Classification of Triangle Measurement & Perimeter
In this classification of triangles worksheet, 10th graders identify and complete 8 different problems that include determining the measurement and perimeter of various types of triangles. First, they color all right, acute, and obtuse...
Curated OER
Toothpick Triangles
Students draw a chart (included in the lesson) to use with their investigation. They review terminology of triangles and receive toothpicks to use in the lesson. Beginning with three toothpicks, students form a triangle. They complete...
Curated OER
2-Dimensional Shapes: Drawing Shapes
Some of the best practice with shape identification comes from drawing the figures first-hand. Young geometers draw nine two-dimensional shapes: rectangle, circle, square, pentagon, hexagon, octagon, triangle with three equal sides,...
Curated OER
Right Triangles
In this right triangles instructional activity, 10th graders solve and complete 12 various types of problems. First, they solve for x given each of the right triangles shown. Then, students determine the length of the shorter diagonal...
Curated OER
Triangles
Why are there so many different types of triangles? Be that as it may, beginning geometers need to understand the differences between equilateral, isosceles, scalene, and right triangles, and they get a visual approach with this...
Curated OER
Easy Worksheet: Classify the Triangle
In this classify the triangle worksheet, students solve 6 short answer problems. Students identify the type of triangle being described according to its angle measures and side lengths.
Mathematics Assessment Project
Solving Problems with Circles and Triangles
After completing a task involving examining the ratio of areas of triangles and circles in a given figure, scholars examine sample responses to identify other strategies they could use to solve the problem.
Curated OER
Investigation - Mathematical Reasoning: Tables and Chairs
Fourth graders draw pictures and diagrams as they attempt to solve a mathematical problem involving the arrangement of eleven tables shaped like equilateral triangles and the seating of exactly twenty-five people.
Curated OER
Area and Perimeter
In this area and perimeter worksheet, 10th graders solve and complete 18 various types of geometry problems. First, they find the area of a figure shown with consecutive sides perpendicular. Then, students find the area and perimeter of...
National Security Agency
Classifying Triangles
Building on young mathematicians' prior knowledge of three-sided shapes, this lesson series explores the defining characteristics of different types of triangles. Starting with a shared reading of the children's book The Greedy Triangle,...
Curated OER
Geometry Standardized Test Practice
In this angles and figures review worksheet, 10th graders solve and complete 39 different multiple choice problems. First, they find the length of a line between two given points. Then, students name the type of transformation and the...
Curated OER
Geometry Journal: Isosceles Triangles
In this isosceles triangles worksheet, students justify and determine the symmetry of an isosceles triangle. They explore the bisector of rectangles. This three-page worksheet contains two problems. Answers are listed on page three.
Curated OER
Geometry of Triangles - Week 6
In this triangle worksheet, students explore the characteristics of triangles. They find the area of a pentagon, lengths of the sides of a triangle and the area of a quadrilateral. This two-page worksheet contains seven problems.