Curated OER
Area of a Triangle
Students solve the area of triangles. For this precalculus lesson, students are given two sides of a triangle and asked to calculate the area. They apply the law of sine and the side-angle-side area formula to solve.
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...
Illustrative Mathematics
Right Triangles Inscribed in Circles II
So many times the characteristics of triangles are presented as a vocabulary-type of lesson, but in this activity they are key to unraveling a proof. A unique attack on proving that an inscribed angle that subtends a diameter must be a...
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.
Curated OER
Angles Activities
A series of geometry worksheets have mathematicians constructing, dissecting, overlapping, and measuring as they analyze angles in various contexts. Learners use symmetry and reflections in a compass rose to write instructions on...
EngageNY
Using Trigonometry to Determine Area
What do you do when you don't think you have enough information? You look for another way to do the problem! Pupils combine what they know about finding the area of a triangle and trigonometry to determine triangle area when they don't...
Noyce Foundation
Parallelogram
Parallelograms are pairs of triangles all the way around. Pupils measure to determine the area and perimeter of a parallelogram. They then find the area of the tirangles formed by drawing a diagonal of the parallelogram and compare their...
Curated OER
Exploring and Using Shapes to Make a Dance
Second graders use their bodies to create various shapes to make a dance when given various music and beats. In this shapes and dance lesson plan, 2nd graders create lines, curves, twists, and angles with their bodies.
Curated OER
Triangles
For this triangles worksheet, 4th graders study the lengths that are stated for 3 triangles and describe each triangle by its sides. Students describe 3 additional triangles by their angles.
Curated OER
Learning About Triangles
Upper graders label four triangles and fill in the labels correctly. They draw three original triangles and answer the questions about them.
Curated OER
Classifying Triangles
If you're looking for a presentation to assist you in your teaching of triangles, this one could be for you. In it, learners are shown how triangles are classified by the size of their angles and by their sides. These are tricky concepts...
Curated OER
Algebra 2 & Trigonometry Practice: Law of Sines
In this law of sines worksheet, students solve 9 multiple choice and short answer problems. Students use the law of sines to missing side lengths and angles of triangles.
Curated OER
Section 2.5 - Problem Solving (Part B)
Trying to figure out the perimeter of a geometric figure? Here are a few word problems to set up algebraic equations to solve for perimeter. There are also some word problems to set up algebraic equations to solve for angles in a...
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...
University of Utah
Geometry: Angles, Triangles, and Distance
The Pythagorean Theorem is a staple of middle school geometry. Scholars first investigate angle relationships, both in triangles and in parallel lines with a transversal, before proving and applying the Pythagorean Theorem.
EngageNY
Triangle Congruency Proofs (part 2)
Looking to challenge your young scholars that have mastered basic triangle congruence proofs? A collection of proofs employ previously learned definitions, theorems, and properties. Pupils draw on their past experiences with proofs...
EngageNY
Law of Sines
Prove the Law of Sines two ways. The ninth segment in a series of 16 introduces the Law of Sines to help the class find lengths of sides in oblique triangles. Pupils develop a proof of the Law of Sines by drawing an altitude and a second...
Corbett Maths
Constructing SAS Triangles
Two sides and an angle ... a triangle it makes. Given the measure to two sides and the angle between them, the narrator of a short video shows how to draw a triangle with a ruler and protractor. Pupils use handouts to practice the newly...
EngageNY
End-of-Module Assessment Task: Pre-Calculus Module 4
Challenge your scholars to show what they know about the Law of Sines, Law of Cosines, and inverses. The six-question assessment is the last in a series of 16. Pupils find the area of triangles and show that the Law of Sines and Law of...
Mathed Up!
Angles in Polygons
Show your class that finding angle measures is a regular calculation with a resource that provides 12 problems dealing with the measures of angles in regular polygons. Pupils use formulas for the sum of measures of angles in a polygon to...
Concord Consortium
Rectangle Space
Take a coordinated look at rectangles. The task asks pupils to plot the length and width of created triangles in the coordinate plane. Using their plots, scholars respond to questions about rectangles and their associated points on the...
Curated OER
Exploring Congruent Triangles
In this congruent triangles worksheet, learners solve 12 different equations related to writing a correspondence statement for triangles in the given diagrams. They complete each correspondence statement and write a congruence statement...
Curated OER
A Rectangle in the Coordinate Plane
A quadrilateral is drawn on the coordinate plane, and eighth grade geometers find the length of each side and the diagonals by applying the Pythagorean theorem.
Curated OER
SuperShapes, Part 1; "Tri"ing Triangles
An outstanding lesson on triangles awaits your math scholars. Learners focus on the triangle, which is the strongest of all polygons. They see the role that triangles play in the design of buildings, and learn about triangle...