Geometry - Third Edition

Chapter 3: Triangle Theorems

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http://www.mathsisfun.com/geometry/interior-angles-polygons.html
NEW This page illustrates the sum of interior angles for triangles, and several other shapes.

http://www.mathopenref.com/triangleinternalangles.html
NEW This interactive applet shows how the sum of the interior angles for any triangle always add to 180 degrees.

http://www.regentsprep.org/regents/math/geometry/GP7/indexGP7.htm
NEW This page contains explanations and practice problems on several triangle inequality theorems.

http://www.regentsprep.org/Regents/math/geometry/GP3b/indexGP3b.htm
NEW This page contains an example and practice of indirectly proving a statement by contradiction.

http://www.mathopenref.com/triangleinequality.html
This page contains an explanation of the triangle inequality theorem with a movable triangle to demonstrate.

http://www.quia.com/cm/94303.html?AP_rand=1353796656
This site has a game to practice determining if a triangle could exist based on the length of its sides.

http://www.freemathhelp.com/feliz-congruent-triangles.html
This page defines congruent triangles and the qualifications for them and lists the methods for proving congruency.

http://www.regentsprep.org/Regents/math/geometry/GP3b/indexGP3b.htm
NEW This page contains several links to definitions, examples, and practice for identifying congruent triangles.

http://www.sparknotes.com/math/geometry2/congruence/section2.rhtml
This page details the different methods on how to prove triangles congruent.

http://www.themathpage.com/atrig/isosceles-right-triangle.htm
This page discusses the isosceles right triangle theorem and has interactive questions.