MATHEMATICS AND ORIGAMI

Jesús de la Peña Hernández

1.2.9 PERPENDICULAR LINES.

1- If edge a is folded over itself, the folding line becomes perpendicular to that edge.

This can be expressed as: A → A; a → a.

2- If an existing fold (mountain) is folded over itself by means of a valley fold, both,

mountain and valley folds become perpendicular.

1.2.10 STRAIGHT LINE PARALLEL TO ANOTHER THROUGH ONE POINT.

1- Get the parallel to existing fold a, through point P.

2- Get b perpendicular to a through P (P → P; a → a).

3- Get through P the perpendicular to b: the answer is c, parallel to a.

1.2.11 TRANSPORTATION OF A SEGMENT OVER A STRAIGHT LINE

1- Transport segment AB, situated on an existing fold line, over the other fold a.

2- Fold the bisector of lines a / AB to get points A ́ B ́ which are the answer.

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