CPCTC
Units & Measurements abbreviation · Math
| Stands for | Corresponding parts of congruent triangles are congruent |
|---|---|
| Categories | Units & Measurements |
CPCTC stands for Corresponding parts of congruent triangles are congruent, a math abbreviation.
A justification used in US high school geometry proofs: once two triangles are shown congruent (by SSS, SAS, ASA, AAS or HL), every pair of matching sides and angles is congruent too.
Example: Triangle ABC is congruent to triangle DEF by SAS, so angle C equals angle F by CPCTC.
Usage notes
CPCTC can only be cited after triangle congruence has been established, a frequent error in two-column proofs. The acronym is largely an American textbook convention; other curricula state the property without it. Some books write CPCF for congruent figures in general.