What is CPCT?Give me a detailed brief about cpct?


Here is the answer to your query.
CPCT stands for corresponding parts of congruent triangles.
It means that if two triangles are congruent with any of SAS, ASA, SSS and RHS congruence rules then remaining angles and sides corresponding in both triangles are equal.


Given: ABCD is a parallelogram. E is the mid point of BC. AB is produced to L.
To prove:   (i) ∆DEC ≅ ∆LEB
  (ii) CD = BL, DE = EL
Proof: In ∆DCE and ∆LBE
∠DEC = ∠LEB   (Vertically opposite angles)
CE = BE       (E is the mid point of BC)
∠DCE = ∠LBE  (Pair of alternate angles since AB||CD)
∴ ∆DEC ≅ ∆LEB   (ASA Congruence Criterion)
CD = BL    (c.p.c.t)
DE = EL      (c.p.c.t)

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 corresponding parts of congruent  triangles

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corresponding parts of congruent triangles

wen 2 triangfles are proved congruent then all parts of triangle are equal to each other

when we have to write it done we have to explain examiner how we got it so we write CPCT instead of corresponding parts of congruent triangles

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 corresponding parts of congruent triangles.

when two triangles are proved equal then all parts of triangle are equal to each other

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C P C T stands for Corresponding Parts of Congruent Triangles are Congruent.  C P C T states that if two or more triangles are proven congruent by: ASA, AAS, SSS, HL, or SAS, then all of their corresponding parts are congruent as well.        C P C T is especially useful in proving various geometrical problems and theorems.


triangle ABC cong triangle DEF,

then the following statements are true:

overline{AB} cong overline{DE},
overline{BC} cong overline{EF},
overline{AC} cong overline{DF}
 angle BAC cong angle EDF,
 angle ABC cong angle DEF,
 angle BCA cong angle EFD.,



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