Texas Instruments
Identifying a Triangle by its Sides and Angles
Identify triangles by their angle measures and side lengths by looking at and measuring angle measures and side lengths. Use Cabri Jr. to construct various triangles, then manipulate the construction to create the 6 types of triangles,...
EngageNY
An Area Formula for Triangles
Use a triangle area formula that works when the height is unknown. The eighth installment in a 16-part series on trigonometry revisits the trigonometric triangle area formula that previously was shown to work with the acute triangles....
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...
Alabama Learning Exchange
What You Know About the Bermuda Triangle?
Get lost in the classifications. Using the backdrop of the Bermuda Triangle, pupils classify it by angle and side measures. They also learn information about the triangle and its history.
CK-12 Foundation
Pythagorean Theorem to Classify Triangles: Missing Angles
Learn to use the Pythagorean Theorem with non-right triangles. Pupils use the interactive to discover the relationship between the lengths of sides for acute and obtuse triangles. They compare the squares of the sides of the triangles to...
Math Mammoth
Triangles 1
In this triangles learning exercise, students measure and calculate the measurements of eight triangles, their sums and classify the triangles as acute, obtuse or right.
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
The Pythagorean Theorem and Classifying Triangles
Through the examination of the relationship between the lengths of the sides of a triangles students will learn the classification of triangles (acute, right, or obtuse).
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.
Curated OER
Classifying Triangles
In this classifying triangles worksheet, students explore given lengths or angle measurements and then classify each triangle as isosceles, scalene or equilateral. They also determine if the triangle may be right, acute or obtuse. This...
Curated OER
Travel Triangles
Students demonstrate and understanding of the three types of angles using triangles and quadrilaterals. In this angles lesson plan, students learn about acute, obtuse and right angles. They use cut-outs to find the areas of triangles and...
Bowland
Rods and Triangles
Scholars explore triangles with rods of different lengths. Using rods of 2, 4, 6, 8, and 10 cm class members build as many different types of triangles as they can. They also describe properties of these triangles and determine...
Curated OER
Geometric Properties
Students find triangular angles using the angle theorem. In this geometry lesson, students describe labeled triangles, use the pythagorean theorem, and rewrite information about triangles in standard form.
Concord Consortium
Always, Sometimes, Never
Do your learners always, sometimes, or never remember the properties of the segments in triangles? Get that number closer to always with a creative lesson analyzing all four segments. Scholars consider a statement about one of the...
Curated OER
Indirect Proof and Inequalities in one Triangle
In this geometry worksheet, 10th graders complete an indirect proof and order the sides or angles of a triangle. Also, students determine if a triangle can have sides with the given lengths. The two page worksheet contains twelve...
Curated OER
Triangles
In this triangles learning exercise, 10th graders solve and complete 22 different problems related to various types of triangles. First, they name the shortest and longest sides and the smallest and largest angles in each of triangles...
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
Triangle Angle Sort
In this triangle and angle worksheet, 10th graders identify 36 different angles and triangles illustrated on the sheet. First, they define the vocabulary to include equilateral, scalene, right, and isosceles triangle. In addition, they...
Willow Tree
Common Geometric Figures
Geometry could be called the study of figures. An overview of the figures found in a typical geometry course contains a study of different triangles, quadrilaterals, and regular polygons.
Curated OER
Parts of Similar Triangles
In this parts of similar triangles worksheet, 10th graders solve and complete 15 different statements related to naming the parts found in similar triangles. First, they identify each definition stated that describes an everyday usage of...
Curated OER
Geometry Worksheet: Angle (2)
In this geometry worksheet, students find the measure of missing angles. They identify alternate angles. This one-page worksheet contains two problems.
Curated OER
Constructions and Angles
For this triangle constructing and classifying worksheet, students read through a tutorial on triangles and angles. Then, students complete 17 exercises in which they answer questions about angles and triangles. By clicking on the...
Curated OER
Identify triangles
Students explore triangles. In this geometry lesson plan, students will create note cards with pictorial depictions of right, acute,obtuse, scalene, isosceles, equilateral and equiangular triangles. Students will verbally describe each...
Curated OER
Classifying Triangles
In this classifying triangles worksheet, 10th graders solve 6 different problems related to the classification of triangles either by their angles or by their sides. First, they use a protractor and a ruler to draw triangles using the...