A chord that goes through the center of a circle diameter
Common external tangent A line that is tangent to more than one circle but does not cross between the circles Common external tangent
A segment from the center of a circle to any point on the circle radius
A line that intersects a circle in two separate points. secant
A line that intersects a circle in only one point tangent
The point where a tangent intersects a circle Point of tangency
Common internal tangent A line that is tangent to more than one circle and crosses in between the two circles. Common internal tangent
Externally tangent circles Circle that intersect in only one point and have no other points in common Externally tangent circles
Circles with the same center but differing radii Concentric circles
Internally tangent circles Circles that intersect in only one point with one circle inside of the other (sharing interior points) Internally tangent circles
An angle whose vertex lies on the circle Inscribed angle
An arc measuring less than 180° Minor arc
An arc whose endpoints lie on a diameter of a circle semicircle
Find x 110° 120° A B AB is a diameter X = 60° X = 70°