Illustrative Mathematics
Illustrative Mathematics: 6.g Same Base and Height, Variation 2
This is the second version of a task asking students to find the areas of triangles that have the same base and height. This presentation is more abstract as students are not using physical models. They still determine the area of each...
Illustrative Mathematics
Illustrative Mathematics: 6.g Polygons in the Coordinate Plane
The purpose of this task is for students to practice plotting points in the coordinate plane and finding the areas of polygons. This task assumes that students already understand how to find areas of polygons by decomposing them into...
Mangahigh
Mangahigh: Shape: The Angles Inside a Triangle
Test your knowledge of the missing angle measure.
Mangahigh
Mangahigh: Shape: Types of Triangle
Test your knowledge of triangles by identifying the different types.
Mangahigh
Mangahigh: Shape: Proof of the Sum of the Angles in a Triangle
Determine that all angles in a triangle equal 180 degrees.
Mangahigh
Mangahigh: Shape: Proof of the Exterior Angle Theorem for a Triangle
Use your knowledge of exterior angles of a triangle to prove the theorem.
CK-12 Foundation
Ck 12: Geometry: Unknown Dimensions of Triangles Grade 6
[Free Registration/Login may be required to access all resource tools.] Find the unknown dimensions of a triangle given its area and another dimension.
CK-12 Foundation
Ck 12: Geometry: Unknown Dimensions of Triangles Grade 7
[Free Registration/Login may be required to access all resource tools.] Find unknown dimensions of triangles given area and one other dimension.
CK-12 Foundation
Ck 12: Trigonometry: Identify Accurate Drawings of Triangles
[Free Registration/Login may be required to access all resource tools.] Determine if diagrams of triangles are accurately drawn.
CK-12 Foundation
Ck 12: Geometry: Hl Triangle Congruence
[Free Registration/Login may be required to access all resource tools.] In this lesson students prove two right triangles are congruent with the Hypotenuse-Leg shortcut. Students examine guided notes, review guided practice, watch...
CK-12 Foundation
Ck 12: Geometry: Third Angle Theorem Grades 8 10
[Free Registration/Login may be required to access all resource tools.] Apply the Third Angle Theorem.
CK-12 Foundation
Ck 12: Elem Math: Classify Triangles, Composite Figures Number of Equal Sides
[Free Registration/Login may be required to access all resource tools.] Students watch a video overview and attempt practice problems on classifying a triangle inside a composite figure.
CK-12 Foundation
Ck 12: Elem Math: Classifying Right Obtuse or Acute by Angle Measure
[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems on how to classify triangles based on angle measures.
CK-12 Foundation
Ck 12: Elem Math: Counting the Number of Basic 2 D Shapes in a Set of Figures
[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems on identifying various 2D shapes in a set of figures.
Math Is Fun
Math Is Fun: Trigonometric Identities
A good introduction to trigonometric identities, equations that are always true for a right triangle and require knowledge of the functions sine, cosine, and tangent.
Math Is Fun
Math Is Fun: Solving Triangles
Find guidelines to help you "solve" triangles, which means finding the value of missing sides and angles. Provided are examples of six scenarios in which you can solve a triangle's missing measurements, as well as relevant equations,...
Discovery Education
Discovery Education: Web Math: Find Out Things About a Right Triangle
Gives basic info about a right triangle. Also students can substitute values for sides or angles in order to find missing values. The method for solving is then explained.
That Quiz
That Quiz
ThatQuiz is an excellent assessment tool for teachers and students. At this site, teachers can create individualized or group assessments on a variety of math topics. Students take these practice assessments directly online and receive...
Khan Academy
Khan Academy: Solve Triangles Using the Law of Sines
Solve missing triangle measures using the law of sines. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
CK-12 Foundation
Ck 12: Geometry: Altitudes Intermediate
[Free Registration/Login may be required to access all resource tools.] This concept teaches students properties of altitudes of triangles and how to apply them.
CK-12 Foundation
Ck 12: Geometry: Third Angle Theorem Grades 9 10
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to the Third Angle Theorem.
CK-12 Foundation
Ck 12: Geometry: Triangle Proportionality Grades 9 10
[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to determine if lines in triangles are parallel and find missing lengths using the Triangle Proportionality Theorem.
CK-12 Foundation
Ck 12: Geometry: Angle Measures in Given Triangles
[Free Registration/Login may be required to access all resource tools.] Find the degree measure of an unknown angle in given triangles.