Proposition: 1.36: Parallelograms on Equal Bases and on the Same Parallels
Euclid's Formulation
Parallelograms which are on equal bases and between the same parallels are equal to one another.
 Let $ABCD$ and $EFGH$ be parallelograms which are on the equal bases $BC$ and $FG$, and (are) between the same parallels $AH$ and $BG$.
 I say that the parallelogram $ABCD$ is equal to $EFGH$.
Modern Formulation
Parallelograms (\(\boxdot{ADCB}\) , \(\boxdot{EHGF}\)) on equal bases (\(\overline{BC}\), \(\overline{FG}\)) and standing between the same parallels (\(\overline{AH}\), \(\overline{BG}\)) are equal in area.
Table of Contents
Proofs: 1
Mentioned in:
Proofs: 1 2 3 4 5
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References
Adapted from CC BYSA 3.0 Sources:
 Callahan, Daniel: "Euclidâ€™s 'Elements' Redux" 2014
Adapted from (Public Domain)
 Casey, John: "The First Six Books of the Elements of Euclid"
Adapted from (subject to copyright, with kind permission)
 Fitzpatrick, Richard: Euclid's "Elements of Geometry"