Cpctc

Math

Definition

An abbreviation for 'Corresponding Parts of Congruent Triangles are Congruent.' Once two triangles are proven congruent (by SSS, SAS, ASA, AAS, or HL), every pair of corresponding sides and angles must also be congruent.

Examples

  • After proving △ABC ≅ △DEF by SAS, you can conclude AB = DE by CPCTC
  • In a proof that a quadrilateral's diagonal bisects an angle, you first prove two triangles congruent, then use CPCTC on the angles

Related Terms

Triangle congruence postulates Two-column proofs Isosceles triangle theorem Parallelogram properties

Study This Concept

Practice CPCTC with free review games in these units:

Geometry Unit 4: Congruent Triangles