Circle-a closed curve in. a plane all of whose points are equally distant from a fixed point in the plane called the center

Circumference-the perimeter of a circle

Semicircle-one half of a circle

Diameter-a line throught the center with its ends on the circle

Radius-a line joining the center with any point on the circle

Chord-any straight line whose ends are on the circle

Arc-any portion of a circle

Quadrant-the arc which represents a quarter of a circle

Congruence-two plane figures are congruent if they have the same size and shape

Corresponding parts-the angles and sides that match

Axiom-a general statement acceptex without proof to be true

Postulate-a geometric assumption accepted without proof to be true

Proof-the process of deductive reasoning whereby the truth of a theorem or correctness of a construction is established

Given-a statement of beginning facts

Prove-what is to be shown true

Analysis-planning and reasonin gto discover how to solve a proof

Proof-logically arranged steps leading to the conclusion

Corollary-another geometric statement that is easily deduced from the given theorem