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 have a recipe for confusion.
Fortunately, an interactive notebook can not only keep the terms in an easy to reference location, but it can help tactile and kinesthetic learners connect with the vocabulary.
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