This activity is also part of one or more other Books. Modifications will be visible in all these Books. Do you want to modify the original activity or create your own copy for this Book instead?
This activity was created by '{$1}'. Do you want to modify the original activity or create your own copy instead?
This activity was created by '{$1}' and you lack the permission to edit it. Do you want to create your own copy instead and add it to the book?
Angle extérieur (Cercle)
Propriété : Dans un cercle, la mesure d'un angle situé à l'extérieur de celui-ci est égale à la demi-différence des mesures des arcs interceptés.