Congruent Triangles

Overview Classify triangles by sides and angles. Discover special properties of isosceles and equilateral triangles. Learn how to prove triangles are congruent using SAS, SSS, ASA, AAS, and HL. Angles of Triangles Classify triangles by sides and angles. Learn the terminology like remote interior angles. Section 5.1 Notes Congruent Polygons Section 5.2 Notes Isosceles [...]

By | 2017-11-13T22:01:57+00:00 November 18th, 2015|Geometry|0 Comments


Translations Translations are one type of transformation. With translations, a pre-image is moved left or right, up or down. It preserves its size, shape, and angle measures. Vectors are used to show how a preimage has moved to the new image. The video below and the accompanying notes sheet can help you understand translation notation. [...]

By | 2017-11-13T22:02:00+00:00 October 29th, 2015|Geometry|0 Comments

Angle Relationships

Sometimes the hardest part of Geometry is the foreign language in which it is delivered. Angles can be acute, obtuse, right, straight, complimentary, supplementary, adjacent, vertical, congruent, and can have common sides with one another or non-common sides. Add terms like opposite rays and make a distinction between congruence and having equal measures and you [...]

By | 2017-11-13T22:02:01+00:00 August 4th, 2015|Geometry|0 Comments

Midpoint and Distance Formulas

The midpoint formula and the distance formula are introduced in algebra class. If students do not get a chance to discover how they are derived, they become yet another set of equations and processes to memorize. The activity below gives students an opportunity to discover the formulas or re-discover them. The Pythagorean Theorem is sprinkled [...]

By | 2017-11-13T22:02:01+00:00 July 16th, 2015|Algebra, Geometry|0 Comments

Ruler and Segment Addition Postulates

Most geometry books start with the fundamentals which can be confusing for students because the math itself is so easy. After working through the abstractness that is algebra, when we ask students to perform some simple addition and subtraction they wonder, "What's the catch?". The initial focus is on "teaching the rules" of geometry and [...]

By | 2017-11-13T22:02:01+00:00 July 14th, 2015|Geometry|0 Comments

Points, Lines, and Planes

Terminology and Symbols The concepts of points, lines, planes, line segments, and rays are crucial for creating a great foundation on which to understand Geometry. The symbolism is particularly important. Geometry starts with three undefined terms - words with no formal definition but with a common agreement of what they are. A Point is a place [...]

By | 2017-11-13T22:02:01+00:00 July 13th, 2015|Geometry|0 Comments

Let’s Go Fly a Kite!

Build Your Own Kite.pdf contains a printable version of the graphic above for classroom use. How High is that Kite? can help start a discussion on flying kites. Similar Kites asks students to find the measurements for a smaller and a larger kite. In the video and photo from How High is that Kite? the kite's string was completely [...]

By | 2017-11-13T22:02:02+00:00 March 21st, 2015|Geometry|2 Comments

How High is that Kite?

There is nothing quite like flying a kite on one of the first breezy days of spring. Is it possible to determine how high a kite is flying from a photograph? What would you need to know? If you were flying a kite, what tools could you use to determine its height?     [...]

By | 2017-11-13T22:02:02+00:00 March 21st, 2015|Algebra II, Geometry, Uncategorized|0 Comments

Just How Tall Was That Snowman?

You have to love people who make lemonade from lemons. A recent photo circulating in FaceBook made me envious, for just a fraction of a second, of the people in Boston who are dealing with the historic snow falls of the 2014-2015 winter. Snow Pit, South Boston, MA. 2015. Courtesy Bill McKay   The [...]

By | 2017-11-13T22:02:02+00:00 February 28th, 2015|Geometry, PreCalculus|1 Comment