The angle bisector theorem is commonly used when the angle bisectors and side lengths are known. It can be used in a calculation or in a proof. An immediate consequence of the theorem is that the angle bisector of the vertex angle of an isosceles triangle will also bisect the opposite side.
Predator and prey populations affect each other because if a predator of one prey kills that one animal than that animal dies and the prey decrease by one and when one predator dies from being killed or just naturally dying, then the predators decrease by one.
Blood types A and B are similar to each other because they both have antigen on red cells.
Blood type AB has both A and B antigens on red cells.
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