Unit 1 Circles
center of an arc
The center of the circle that contains the arc.
center of a circle
The point in the plane equidistant from all points of the circle.
central angle
An angle with its vertex at the center of a circle.
chord
A segment with endpoints on the circle.
circle
The set of all points in a plane that are at a given distance from a given point in the plane.
circumscribed polygon
A polygon with each side tangent to the circle contained within.
common external tangent
A tangent to two coplanar circles such that a segment connecting the centers of the circles does not intersect the tangent.
common internal tangent
A tangent to two coplanar circles such that a segment connecting the centers of the circles intersects the tangent.
concentric circles
Two or more circles that lie in the same plane and have the same center.
congruent circles
Circles that have equal radii.
diameter
A chord of a circle that contains the center of the circle.
great circle
The intersection of a sphere and a plane that passes through the center of the sphere.
inscribed angle
An angle with vertex that is a point of an arc other than the endpoints and with sides that pass through the endpoints of the arc.
intercepted arc
The arc with endpoints that are points of the sides of the angle and including all points on the arc in the interior of the angle.
major arc
The union of two points of a circle, not the end points of a diameter; and all points of the circle that lie in the exterior of the central angle with sides that contain the two points.
midpoint of an arc
A point x on the arc ABC such that m AXC = m XBC.
minor arc
The union of two points of the circle, not the ends of a diameter; and all points of the circle that lie in the interior of the central angle with sides that contain the two points.
radius
A segment joining the center of a circle to a point of the circle.
secant
A line that contains a chord of a circle.
secant ray
A ray that lies on a secant line and contains both points of intersection with the circle.
semicircle
The union of the endpoints of a diameter of a circle and all points of the circle lying on the same side of the diameter.
small circle
The intersection of a sphere and a plane that does not pass through the center of the sphere.
sphere
The set of all points at a given distance from a given point.
tangent circles
Two coplanar circles that are tangent to the same line at the same point.
tangent line
A line that lies in the plane of the circle and intersects the circle in exactly one point.
tangent ray
A ray that lies on a tangent line and contains the point of tangency.
Unit 2 Area and Volume
apothem
A segment from the center of a regular polygon perpendicular to a side.
area
A real number that measures the space inside a region.
circumference
The distance around a circle.
cone
A solid figure with a circular base and sides tapering to a point.
cubic unit
The unit used to measure volume. It is a cube that measures one linear unit on a side.
cylinder
A solid figure with two congruent parallel circles as bases.
lateral area
The area of the sides of a solid figure.
length of arc
The measure of an arc in linear units.
pi
The ratio of the circumference to the diameter in any circle.
prism
A solid figure with two congruent parallel polygons for bases.
pyramid
A solid figure with one polygon for a base and triangular sides.
region
The space bounded by the sides of a polygon.
sector of a circle
The part of a circle bounded by two radii and an arc.
segment of a circle
The part of a circle bounded by a chord and its arc.
slant height
The length of an altitude of a side of a pyramid.
square unit
A unit that measures area. It is a square that measures one linear unit on a side.
total area
The sum of the lateral area and the area of the base(s).
Unit 3 Coordinate Volume
coordinate axes
The x-axis and the y-axis arranged to intersect at right angles at the zero point on each axis.
origin
The intersection of the coordinate axes at (0, 0).
slope
The ratio of the difference in the y-coordinate to the difference in the x-coordinates of any two points on a line; .
x-axis
The horizontal axis in the coordinate axes.
y-axis
The vertical axis in the coordinate axes.
Unit 4 Transformations
coordinate axes
The x-axis and the y-axis arranged to intersect at right angles at the zero point on each axis.
origin
The intersection of the coordinate axes at (0, 0).
slope
The ratio of the difference in the y-coordinate to the difference in the x-coordinates of any two points on a line; .
x-axis
The horizontal axis in the coordinate axes.
y-axis
The vertical axis in the coordinate axes.