Points in a plane equidistant from a given center
Circle
Cirlcles that have the same radius
Congruent circles
Distance from center to a point on the circle
Radius
Distance across a circle, through center
Diameter
Segment with end points on a circle
Chord
A line that intersects a circle in two points
Secant
A line that intersects a circle I’m exavrly one point
Tangent
Part of a circle (circumference) that measures less than 180*
Minor arc
2€r
Circumference
Part of a circle (circumference) that measure greater than 180*
Major arc
Part of a circle (circumference) that measures exactly 180*
Semi-circle
Angles that are formed by two line segments that have a vertex on the center
Central angles
Arc formed by an angle inside the arc
Intercepted arc
(Tan)^2=o•ws
Secant-tangent
A•b=c•d
Intercepting chord
1/2(big arc + small arc)
Exterior interception
A(a+b)=c(c+d)
Secant- secant
tangent=tangent
Tangent-tangent
1/2(arc +arc)
Interior interception
(0/360) 2€r
Arc length
(0/360)€r^2
Area of a sector
Angle=1/2 arc
Tangent- chord
Opp. Angles supplementary
Inscribed quadrilateral
coplaner circles with the same center
Concentric circles
(o/360) €r^2 - 1/2 bh
area of a minor arc