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acute angle angle less than 90 degrees
obtuse angle angle greater than 90 degrees
right angle angle equaling 90 degrees
acute triangle triangle with all acute angles
obtuse triangle triangle with one obtuse angle
right triangle triangle with one right angle
scalene triangle triangles whose sides are all different measures
isosceles triangle triangle with two sides that are congruent
equilateral triangle triangle with all three sides congruent
equiangular triangle triangle with three congruent angles
The measure of an angle in an equilateral or equiangular triangle 60 degrees
The sum of all angles in a triangle 180 degrees
exterior angle of a triangle angle formed by one side of a triangle and the extension of another side
remote interior angles interior angles not adjacent to a given exterior angle
congruent triangles triangles that have corresponding parts congruent
congruence transformations occurs when a slide flip or turn of a triangle does not change the size or shape
included angle angle formed by two sides of a triangle
SSS Postulate If the sides of one triangle are congruent to the sides of another triangle then the two triangles are congruent.
SAS Postulate If two sides of a triangle and their included angle are congruent to two sides of another triangles and their included angle then the triangles are congruent.
included side the side between two angles of a triangle
ASA Postulate If two angles and the included side of one triangle are congruent to two angles and the included side of another triangle then the two triangles are congruent.
AAS Postulate If two angles and a nonincluded side of one triangle are congruent to the corresponding angles and side of a second triangle then the two triangles are congruent.
SSA Postulate a valid test of congruence for right triangles
base angles two angles formed by the base and the congruent sides of an isosceles triangle
vertex angle angle formed by the two congruent sides of an isosceles triangle
coordinate proof uses figures in the coordinate plane and algebra to prove geometric concepts
Created by: Elive
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