PPT-4.2: Angle Relationships in Triangles

Objectives Find the measures of interior and exterior angles of triangles Apply theorems about the interior and exterior angles of triangles Supplies Math Notebook Textbook Assignment p 228 1523skip 17 2932. Using scissors and a ruler, cut out a triangle from a piece of colored paper. Clean up your area afterwards. We will be using the triangle during our lesson today. . Constructing Triangles. Common Core 7.G.2. Holt Geometry. Warm Up. Lesson Presentation. Lesson Quiz. Warm Up. Construct each of the following.. 1.. . A perpendicular bisector.. 2.. An angle bisector.. 3.. Find the midpoint and slope of the segment . July 2011. Subject Content = Covered. We are working on applications. Multistep and practical problems. 3 Dimensional problems. Setting out the steps in a logical and clear manner, which may include drawing triangles. Talya Eden, . Tel Aviv . University. Amit Levi, . University of Waterloo. Dana . Ron, . Tel Aviv . University. C. . Seshadhri. , . UC Santa Cruz. Counting Triangles. Basic graph-theoretic algorithmic . 4.2. SSS Postulate (Just call it SSS). If . three sides of one triangle . are congruent to. three sides of another triangle, . then the triangles are congruent.. SAS Postulate (Just call it SAS). If . A. . = . B. . C. . D. . = .  . Warm-Up. ~Write one sentence explaining what answer you chose.. ~Write one sentence explaining what answers you were able to eliminate.. Polygons and Triangles. The word polygon means many (poly) angles (gon). This includes triangles, squares, rectangles, trapezoids, parallelograms, . Helpful websites. http://www.regentsprep.org/Regents/mathb/1c/preprooftriangles.htm. http://www.mathwarehouse.com/geometry/congruent_triangles/. http://www.cliffsnotes.com/WileyCDA/CliffsReviewTopic/Congruent-Triangles.topicArticleId-18851,articleId-18788.html. If triangles are similar are other things similar as well. Proportional Parts Conjecture. If two triangles are similar, then the length of the corresponding altitudes, medians, and angle bisectors are proportional to the lengths of the corresponding sides. This shows similar Triangles. Constructing Triangles. Common Core 7.G.2. Vocabulary. Uniquely defined. Ambiguously defined. Nonexistent. Triangle Inequality Theorem. Let’s review what we learned yesterday with this video. . http://. Using Congruent Triangles. Congruent triangles have congruent corresponding parts. So, if you can prove the two triangles are congruent then you know their corresponding parts must be congruent as well.. Warm Up. 1. . Find each angle measure.. True or False. If false explain.. 2.. Every equilateral triangle is isosceles.. 3.. Every isosceles triangle is equilateral.. . 60°; 60°; 60°. True. False; an isosceles triangle can have only two congruent sides.. Lewis Carroll/Charles Dodgson. Some . fun facts:. .. as a mathematician, Dodgson was, in the words of . . Peter Heath: "An inveterate publisher of trifles [who] was forever putting out pamphlets, papers, broadsheets, and books on mathematical topics [that] earned him no reputation beyond that of a crotchety, if sometimes amusing, controversialist, a compiler of puzzles and curiosities, and a busy yet ineffective reformer on elementary points of computation and instructional method. In the higher reaches of the subject he made no mark at all, and has left none since." . Geometry. 5.1 Angles of Triangles. Essential Question. How are the angle measures of a triangle related?. 5.1 Angles of Triangles. November 21, 2016. 5.1 Angles of Triangles. November 21, 2016. Goals – . Magic Triangles. There are 3 magic triangles, two of which are on your formula sheet. They let you do some trigonometric equations without calculators. These are a fundamental part of ”exact solutions” .