Introduction to Circle and other related terms CIRLES Introduction to Circle and other related terms

Terms about a circle A radius of a circle is a segment connecting the center to a point on the circle. A segments whose endpoints lie on the circle is called a chord. A chord that contains the center of the circle is a diameter of a circle. A tangent to a circle is a line coplanar with the circle that intersects the circle in exactly one point. The point is called point of tangency. A secant is a line that intersects the cirlce in two points.

Practice Tangent diameter Secant radius Chord

Practice F Name 5 radii A Name 3 chords E Name 2 diameters Name 1 secant Name 1 tangent Name the point of tangency A E O D B C

Polygons and Circles When a polygons sides are the chords of the circle, then the polygon is an inscribed polygon.

Polygons and Circles When a polygons sides are tangent to the circle, then the polygon is a circumscribed polygon.

Determine if the polygons are inscribed or circumscribed.

Arcs and Angles An arc is a part of the circle. A central angle of a circle is coplanar iwth the circle. Its vertex is the center of the circle. A minor arc is the smaller arc of the circle. A major arc is the larger arc of the circle. A semicircle is equal to the half of a circle. Cocentric circles are coplanar circles that share the same center Inscribed angles are angles that has its vertex on the circle and whose sides contains chords of the circle.

Practice E Name 3 major arc Name 3 minor arc Name 3 central angles A Name 3 inscribed angles Name 2 semicircles A D O B C