EngageNY
Using Trigonometry to Find Side Lengths of an Acute Triangle
Not all triangles are right! Pupils learn to tackle non-right triangles using the Law of Sines and Law of Cosines. After using the two laws, they then apply them to word problems.
Curated OER
Getting it Right! An Investigation of the Pythagorean Theorem
In order to learn about the Pythagorean Theorem, young mathematicians investigate relations and patterns between different sides of a right triangle to look for possible relations among the squared sides. Once they have established the...
Curated OER
Altitude to the Hypotenuse
Can your class solve right triangles and identify the properties common to right triangles? They will investigate and state the relationship between the altitude to the hypotenuse and the two segments of the hypotenuse formed by the...
Education Development Center
Similar Triangles
Model geometric concepts through a hands-on approach. Learners apply similar triangle relationships to solve for an unknown side length. Before they find the solution, they describe the transformation to help identify corresponding sides.
Radford University
The Pythagorean Theorem in Crime Scene Investigation
It's a Pythagorean who-dun-it. Pupils apply the Pythagorean Theorem in several different real-world scenarios involving right triangles. By solving each task, they find the thief who was responsible for a museum heist.
Curated OER
Applications of Triangles
Students apply the properties of a right triangle. In this triangle instructional activity, students describe and compare radians to degrees. They solve problems using the properties and ratios of a right triangle.
Curated OER
Pythagorean Theorem: Triangles and Their Sides
Learners investigate triangles and their relationship to each other. In this geometry lesson, students solve right triangles using the properties of the Pythagorean Theorem. They differentiate between right, acute, straight and oblique...
Curated OER
Pythagorean Theorem
Students discover the Pythagorean Theorem. In this discovering the Pythagorean Theorem lesson plan, students measure the lengths of various triangles to the nearest centimeter. Students record their measurements in a table. Students...
Curated OER
Pythagorean Theorem
Young scholars apply properties of Pythagorean to solve problems. For this geometry lesson, students identify the different parts of a right triangle using ratios. they solve problems using squares and square roots.
Curated OER
Plenty of Pythagoras
Using a twelve foot knotted rope, learners form a 3-4-5 right triangle. Following a discussion of observations about the lengths of the sides of the triangle, students use grid paper, scissors and a centimeter ruler to draw and measure...
EngageNY
Applications of the Pythagorean Theorem
Begin seeing the world through the lens of geometry! Use the 19th installment in a 25-part module to apply the Pythagorean Theorem to solve real-world problems. Individuals sketch situations resulting in right triangles such as the...
Curated OER
Triangle Sum Theorem
Teach your class how to solve problems using the triangle sum theorem. In this geometry instructional activity, young scholars identify the missing angles in a triangle using the sum theorem. They graph triangles on the TI and moves the...
Curated OER
Proving Pythagoras
Learners prove the theorem of Pythagoras. In this Pythagorean Theorem lesson, students define the different parts of a right triangle. They use the Pythagorean Theorem to solve for the missing sides and angles of a right triangle.
Curated OER
Applying the Pythagorean Theorem to find Distances Between Cities
Students solve problems using the Pythagorean Theorem. In this geometry lesson, students identify the Pythagorean Triple and use it to solve real life problems.
Curated OER
Triangle Inequality Theorem
Students use the inequality theorem to solve triangles and their properties. In this geometry lesson, students are given spaghetti of different lengths and asked to create triangles. They conclude the necessary length needed to make a...
Math Stars
Math Stars: a Problem-Solving Newsletter Grade 7
Put on your thinking caps because middle school math has never been more interesting in this huge resource full of thought provoking questions. Written as a newsletter, the resource has 10 two-page newsletters with a variety of...
Curated OER
Pythagorean Theorem and Problem Solving
Students use the Pythagorean Theorem to solve problems. In this geometry lesson, students identify the properties of a right triangle. They find the missing side and angles of a right triangle.
Curated OER
Let's Explore the World of Triangles and Quadrilaterals!
Second graders explore the features of triangles and quadrilaterals. In this lesson on triangles and quadrilaterals, 2nd graders rotate with their group to five different activities all exploring a different aspect of geometry.
Curated OER
Triangle in the Matrix
Young mathematicians represent a triangle with a matrix and use the determinant to find the area of three given triangles. Learners also verify the formula for area of a triangle.
Curated OER
Similar Triangles - Applied Problems
Students differentiate between similar and congruent triangles. In this geometry lesson, students identify the angles of triangles using the similarity theorem. They apply concepts of triangles to the real world.
Curated OER
Concurrent Lines in Triangles
Students explore the concept of concurrent lines in triangles. In this concurrent lines in triangles lesson, students work in groups to investigate properties of concurrent lines in acute, right, and obtuse triangles. Students use a...
Curated OER
Measuring the Egyptian Way using the Pythagorean Theorem
Students measure using the Pythagorean Theorem. In this geometry lesson, students solve right triangles using the properties of the Pythagorean theorem. They apply the same knowledge to solving story problems.
Curated OER
Introduction to Trigonometry
Students identify the six trigonometric ratios and properties. In this trig lesson, students define basic trig functions as it relates to solving right triangles. They identify the equation for sine as o/h and cosine as a/h and tangent...
Curated OER
Chords of a Circle
Teach how to differentiate between chords and perpendicular bisectors. In this geometry lesson, students relate the properties of chords and circle to solving right triangle. They define what makes two chords congruent in side a circle.