Properties of Triangles

Address key vocabulary in the seventh grade Common Core Math Standards with this comprehensive list. A series of word cards is also provided that supports each term with images and examples, making this an excellent tool for teaching the...

Try five problems on triangles. Levels A and B focus on shapes that can be created from right triangles. Level C touches upon the relationship between the area of a six-pointed star and the area of each triangle of which it is composed....

An informative lesson contains a brief explanation of how the sum of the angles of a triangle is a line. The lesson continues with determining the missing angle in a triangle, or solving for a variable. Using the sum of the...

Your visual geometry learners will appreciate triangle drawings as they model the triangle sum theorem and algebraically solve to find the missing interior angle in a triangle. Practice problems increase in complexity and vary in their...

Can any three side lengths create a triangle? Your classes tackle this question and more in the 11th lesson of the 29-part module. Through modeling with patty paper, individuals discover the relationship between the lengths of the sides...

Use the opposite to organize angles or sides. The video provides the relationship of angle measures based on the lengths of sides in a triangle and its converse. Using two triangles, the segment of a larger playlist on geometry shows the...

Square roots connect squares and right triangles. Using the Pythagorean Theorem, the video shows the relationship between the sides and hypotenuse of a 45-45 right triangle. The portion of a larger geometry playlist applies the...

Can any three lengths make a triangle? One of the videos in a playlist on basic geometry introduces the Triangle Inequality Theorem. Using three given lengths, the presentation illustrates the restrictions on lengths of any side of a...

This modern animation and discussion of the ancient secrets of Pascal's triangle manages to be topical, engaging, and mathematically deep all at the same time. A great introduction to the power of number theory across multiple math...

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...