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