Geometry Vocab Ch 4

  1. Acute Triangle
    3 acute angles
  2. Equiangular Triangle
    Three congruent acute angles
  3. Right Triangle
    One right angle
  4. Equilateral Triangle
    Three congruent sides
  5. Scalene Triangle
    No congruent sides
  6. Interior Angle
    formed by two sides of a triangle
  7. Exterior angle
    formed by one side of the triangle and the extension of an adjacent side. Each exterior angle has two remote interior angles
  8. Remote interior angle
    interior angle that is not adjacent to the exterior angle
  9. Corresponding angles + Corresponding sides
    the same position in polygons with an equal number of sides
  10. Congruent polygons
    (example) Two polygons are congruent polygons if and only if their corresponding angles and sides are congruent. Thus triangles that are the same size and shape are congruent
  11. Triangle rigidity
    provides a shortcut for proving two triangles congruent. (example) It states that if the side lengths of a triangle are given, the triangle can only have one shape
  12. Included angle
    Angle formed by two adjacent sides of a polygon
  13. Included side
    Common side of two consecutive angles in a polygon
  14. Angle-Side-Angle (ASA)
    If two angles and the included side of one triangle are congruent to two angles and the included side of another triangle, then the triangles are congruent
  15. Hypotenuse-Leg (HL)
    If the hypotenuse and a leg of a right triangle are congruent to the hypotenuse and a leg of another right triangle, then the triangles are congruent
  16. CPCTC - abbreviation for the phrase “Corresponding Parts of Congruent Triangles are Congruent.”
    Can be used as a justification in a proof after you have proven two triangles congruent
  17. Coordinate proof
    A style of proof that uses coordinate geometry and algebra. The first step of a coordinate proof is to position the given figure in the plane
  18. Legs
    shorter sides of a angle or triangle
  19. Vertex angle
    angle formed by the legs
  20. Base
    opposite side of the vertex angle
  21. Base angles
    two angles that have the base as a side
Card Set
Geometry Vocab Ch 4