+
Worksheet
Curated OER

Triangle Similarity

For Students 10th
In this triangle similarity learning exercise, 10th graders solve and complete 12 different problems that include defining similar and 3 similar statements using only sides and angles. First, they determine if each pair of triangles...
+
Lesson Plan
EngageNY

Similarity

For Students 9th - 10th Standards
Learn similarity through a transformations lens! Individuals examine the effects of transformations and analyze the properties of similarity, and conclude that any image that can be created through transformations is similar. The...
+
Lesson Plan
EngageNY

Congruence Criteria for Triangles—SAS

For Students 9th - 10th Standards
Looking for a different approach to triangle congruence criteria? Employ transformations to determine congruent triangles. Learners list the transformations required to map one triangle to the next. They learn to identify congruence if...
+
Interactive
CK-12 Foundation

Special Triangle Ratios: Special Right Triangle Ratios

For Students 9th - 12th Standards
Go from one side length to any other side length with special right triangles. Individuals use the interactive to investigate the ratio of sides in 45-45 and 30-60 right triangles. Scholars make generalizations about the types of special...
+
Interactive
CK-12 Foundation

Determination of Unknown Triangle Measures Given Area: Jib Sheets

For Students 10th - 12th Standards
Solving triangles is a breeze. Young boat enthusiasts solve problems involving triangles in the context of sails on a boat. They must apply different strategies, including the Law of Cosines and area formulas.
+
Interactive
CK-12 Foundation

Right Triangles, Bearings, and Other Applications: Sailing Race

For Students 9th - 12th Standards
Help your class get their bearings when it comes to right triangles. Pupils determine distances traveled or components given the bearing of a sailboat using an interactive. The scholars develop a sense of finding the bearings of a given...
+
Interactive
CK-12 Foundation

Distance Formula: Right Triangles

For Students 8th - 10th Standards
Go the distance with a far out resource. Individuals use an interactive to create right triangles on a coordinate plane to help find distance between two points. Challenge questions aid them in developing the distance formula.
+
Interactive
CK-12 Foundation

Angle-Angle-Side Triangles: Garden Gate

For Students 10th - 12th Standards
Good fences make good gardens. Individuals use an interactive to see how angles and sides relate in a triangular-shaped garden fence. They apply the Law of Sines to find the length of the garden gate (third side of triangle) given two...
+
Interactive
CK-12 Foundation

Possible Triangles with Side-Side-Angle

For Students 10th - 12th
It's not often that math allows for multiple answers. Young mathematicians identify possible numbers of triangles when given two sides and a non-included angle. An interactive helps with this investigation.
+
Lesson Plan
Curated OER

Geometric Applications

For Teachers 8th - 9th
In this geometry worksheet, students solve 5 word problems. Each of the problems involves finding one side of a right triangle. Story problems relate the Pythagorean Theorem to building ramps, shadows, and the length of a banner.
+
Lesson Plan
Curated OER

Corresponding Sides and Angles of Similar Triangles

For Teachers 9th - 10th
Students differentiate between corresponding sides ad angles of two triangles. In this geometry lesson, students identify the differences as well as the similarities between two triangles. They differentiate between similar and...
+
Activity
Curated OER

Unit Squares and Triangles

For Teachers 9th - 11th Standards
This is an interesting geometry problem. Given the figure, find the area of a triangle that is created by the intersecting lines. The solution requires one to use what he/she knows about coordinate geometry, as well as triangle and angle...
+
Interactive
CK-12 Foundation

Trigonometric Functions and Angles of Rotation: The Triangle in the Circle

For Students 10th - 12th Standards
Go around the unit circle and create triangles. Pupils move a point around the unit circles to visualize the triangle associated with the angle in standard position. The three main trigonometric functions are defined in terms of the legs...
+
Lesson Plan
Curated OER

Review Geometry - Week 8 (Triangles)

For Teachers 11th - 12th
In this triangle worksheet, students use similar figures to find the length of one side of two similar triangles. They find the area of a triangle inscribed in a rectangle. This two-page worksheet contains eight problems.
+
Worksheet
Curated OER

Mid-Segment of a Triangle

For Students 10th - 11th
In this triangle worksheet, students examine triangle diagrams. They determine the perimeter, length of a line, midpoint of a line, and angle measurement from given information. This one-page worksheet contains ten problems.
+
Interactive
CK-12 Foundation

Identifying Sets of Pythagorean Triples: Matching Problem

For Students 8th - 12th Standards
What sets of whole numbers make up the measures of side lengths in right triangles? Pupils use an interactive triangle to learn about Pythagorean triples. Individuals find missing values in triples and learn more about Pythagorean...
+
Unit Plan
1
1
EngageNY

Congruence, Proof, and Constructions

For Teachers 8th - 10th Standards
This amazingly extensive unit covers a wealth of geometric ground, ranging from constructions to angle properties, triangle theorems, rigid transformations, and fundamentals of formal proofs.  Each of the almost-forty lessons is broken...
+
Lesson Plan
Discovery Education

Exploring Geometry

For Teachers 6th - 8th Standards
Middle schoolers construct a three-dimensional model of a city using both similar and congruent figures and geometric transformations. City must have at least ten buildings with each building labeled and may be constructed out of paper...
+
Printables
Virginia Department of Education

High School Mathematics Geometry Vocabulary Word Wall Cards

For Teachers 9th - 10th
Having a good working knowledge of math vocabulary is especially important for geometry learners. Here are 119 pages worth of wonderfully constructed definitions, constructions, formulas, properties, theorems, and postulates. This is a...
+
Worksheet
Math Mammoth

Angles in a Triangle 2

For Students 6th - 8th Standards
Youngsters draw specified angles when given measurements of other angles and discover traits of angles in similar triangles. This one-page activity contains six multi-step problems.
+
Worksheet
Curated OER

Similarity

For Students 10th
For this similarity worksheet, 10th graders solve and complete 14 different types of problems. First, they find the length of each segment given two lines parallel. Then, students find the measure of each segment of a parallelogram...
+
Interactive
CK-12 Foundation

Identify Accurate Drawings of Triangles: Law of Cosines

For Students 10th - 12th Standards
Drawing triangles is easy, even if you have to calculate the exact length of its sides. Scholars use the Law of Cosines to find missing sides of triangles. An interactive helps them check their answers.
+
Interactive
CK-12 Foundation

Angle-Side-Angle Triangles: Caution Tape

For Students 10th - 12th Standards
Don't lose your marbles. Scholars use an interactive to create a triangle that closes off a portion of a sidewalk with loose marbles. The Law of Sines helps them find the side measures of such a triangle.
+
Lesson Plan
Curated OER

Similar Triangles on the Coordinate Plane

For Teachers 9th - 10th
Pupils investigate triangles and their properties. In this geometry lesson, students differentiate between similar and congruent triangles. They use the SSS theorem to help identify the triangles that are similar or congruent.