Chapter 10 - All Flashcards
(41 cards)
Interior of a circle
Points inside of a circle.
Exterior of a circle
Points outside of a circle.
Chord
A segment whose endpoints are on the circle.
Diameter
A chord that passes through the cent of a circle.
Radius
A segment whose endpoints consist of the center of the circle and a point on the circle.
Tangent
If a line intersects a circle at exactly one point, then the line is a tangent of the circle.
Secant
If a line intersects a circle at two points, then the line is a secant of the circle.
Common tangent
A line that is tangent to two circles.
Common external tangent
A common tangent that does not intersect the segment that joins the centers of the circle.
Common internal tangent
A common tangent that intersects the segment that joins the centers of the circle.
Two circles can intersect in 4 different ways…
No points
One point
Two points
All points
Concentric circles
Circles that have the same center.
Congruent circles
Circles with congruent radii or diameters.
If a line is tangent to a circle
Then it is perpendicular to the radius drawn to the point of tangency.
In a plane, if a line is perpendicular to a radius of a circle, at its endpoints on the circle,
Then the line is tangent to a circle.
If two segments from the same exterior point are tangent to a circle,
Then they are congruent.
Inscribed circle
A circle is inscribed in a polygon if each side of the polygon is tangent to the circle.
Circumscribed circle
A circle is circumscribed about a polygon if each vertex of the polygon lies on the circle.
Central angle
An angle whose vertex is the center of the circle.
Minor arc
Consists of the endpoints of the central angle and all points on the circle that are in the interior of the central angle.
Measure of a minor arc
Measure
Semicircle
An arc whose endpoints are the endpoints of the diameter.
Circle
A set of all points in a plane that are equidistant from a given point called the center.
Adjacent Arcs
Two arcs of the same circle are adjacent if they intersect at exactly one point.