C - Math terms glossary

capacity The number of unit cubes or parts of unit cubes that can be fit into a solid. Also called volume.

cartesian plane Name given to the plane containing points identified as ordered pairs of real numbers. Also called coordinate plane.

center of a circle The given point from which the set of points of the circle are all at the same distance.

Every point on this circle is the same distance away from the center point,"C".

center of a regular polygon The point equidistant from the vertices.

center of a sphere  The given point from which the set of points of the sphere are all the same distance.

Every point on this sphere is the same distance away from its center point, "C".

center of symmetry For a rotation-symmetric figure, the center of a rotation that maps the figure onto itself.

centi-  A prefix meaning 1/100.

centimeter  1/100 of a meter.

central angle of a circle  An angle with its vertex at the center of the circle.

Angle A is a central angle of this circle because its vertex is the center point "A".

centroid of a triangle The point at which all medians of a triangle intersect.

The median is a segment that connects a vertex with the midpoint of the opposite side. When you draw all these medians, they will intersect at the centroid. The centroid is also the center of gravity. So any triangle will balance perfectly on the tip of a pin at its centroid point. Give it a try. It's really cool.

certain event  An event with a probability of 1.

chord A segment whose endpoints are on a given circle.

circle  The set of points in a plane that are equidistant from a given point known as its center.

NOTE: It's important to remember that a circle is only the points on the border. Any point on the inside of this border is in the interior of the circle and is part of what we call the circular region.

circle graph A graph in which information is represented using a circle that is cut into sectors to show values of a particular category. Also called a pie graph.

circularity The "circling back" that sometimes occurs when one tries to define basic terms; returning to the word which one is trying to define.

circumference The perimeter of a circle, which is found by multiplying its diameter times pi.

circumscribed circle A circle that is drawn around the outside of a triangle and contains all the vertices of the triangle. A circle is circumscribed about a polygon if each vertex of the polygon lies on the circle.

clockwise  The direction around a circle in which the hands on a clock usually move.

clockwise orientation The orientation "walking" around a figure keeping its interior to the right.

clockwise rotation The direction in which the hands move on a nondigital clock, designated by a negative magnitude.

coefficient  The number by which a certain variable in a term is multiplied.

Ex: 3xy (the 3 is the coefficient)

coincide  To occupy the same position.

coincident lines Lines that contain exactly the same points. We like to think that they lie on top of each other.

collinear points Points that lie on the same line.

column  A vertical line of objects in a rectangular array.

common denominator  A multiple of all the denominators in a problem.

Ex:
Given 1/2, 1/3, 1/4 one common denominator would be 12,
because 2, 3, & 4 all divide into 12 evenly.
24, 36, 48 etc. would also be common denominators but 12 is used most often because it is the smallest, or "least common denominator", and thus is easier to work with.

common tangent A line which is tangent to two or more distinct circles.

Commutative Property of Addition   For any numbers a and b:
a+ b = b + a. Notice the positions of the numbers switch, but the quantities are still equal.

Ex:
3 +4 = 4 + 3
7=7

Commutative Property of Multiplication   For any numbers a and b:
ab = ba. Notice the positions of the numbers switch, but the quantities are still equal.

Ex:
5 x 6 = 6 x 5
30 = 30

Comparison Model for Subtraction x - y is how much more x is than y.

compass An instrument for drawing circles.

complementary angles Two angles the sum of whose measures is 90.

composite number  Any positive integer exactly divisible by one or more positive integers other than itself and 1.

Ex:
6 is a composite number because 2 & 3 divide it evenly as well as do 6 & 1.

concentric circles Two or more circles that lie in the same plane and have the same center.

conclusion The "then" clause of a condition. The result of a deduction in a proof. Also called consequent.

concurrent Two or more lines that have a point in common.

conditional A statement of the form If... Then....

Ex:
If a quadrilateral has four equal sides then it is a rhombus.

cone The surface of a conic solid whose base is a circle.

congruence transformation A transformation that is a reflection or composite of reflections; also called an isometry.

congruent figures  Figures with the same size and shape. Figures which are the image of each other under a reflection, rotation, or translation, or combination of these.

conic solid The set of points between a given region (its base), together with the vertex and the base.

conic surface The boundary of a conic solid.

conjecture An educated guess or opinion.

consecutive angles In a polygon, two angles whose vertices are endpoints of the same side.

consecutive sides In a polygon, two sides with an endpoint in common.

consecutive vertices In a polygon, endpoints of a side.

consequent The "then" clause of a conditional, also called the conclusion.

construction A drawing which is made using only an unmarked straightedge and a compass following certain prescribed rules.

continuous A figure made up of points with no space between them.

contraction  A size change with a magnitude  between 0 and 1.

contradiction A situation in which there exist contradictory statement(s).

contradictory statements Two statements that cannot both be true at the same time.

contrapositive A conditional resulting from negating and switching the antecedent and consequent of the original conditional.

convenient location A general location for a figure on a coordinate plane in which its key points are described with the fewest possible variables.

converse The conditional statement formed by switching the antecedent and consequent of a given conditional.

conversion factor A factor by which one unit can be converted to another.

convex polygon  A polygon in which no diagonals lie outside the polygon.

convex set A set in which every segment that connects points of the set lie entirely in the set.

coordinate The number or numbers associated with the location of a point on a line, a plane, or in space.

coordinate axes A pair of perpendicular coordinatized lines in a plane that intersect at the point with coordinate 0; three mutually perpendicular coordinatized lines in space that are concurrent at the point with coordinate 0.

coordinate graph  Displaying points as ordered pairs of numbers.

coordinate plane Name given to the plane containing points identified as ordered pairs of real numbers. Also called cartesian plane.

coordinatized line A line on which every point is identified with exactly one number and every number is identified with a point on the line.

coplanar Figures that lie in the same plane.

corollary A theorem that is easily proven from another theorem.

corresponding angles Any pair of angles in similar locations in relation to a transversal intersecting two lines.

In this example we see four sets of corresponding angles. 1&5, 2&6, 3&7, 4&8 If the lines cut by the transversal are parallel, all correspondig angles will be congruent.

corresponding parts Angles or sides that are images of each other under a transformation.

corresponding sides  Any pair of sides in the same relative positions in two similar figures.

Ex: The segment stretching from A to B correspondS to the segment stretching from D to E.

cosine of an angle The ratio leg adjacent to the angle divided by the hypotenuse in a right triangle. Abbreviated cos.

count  A number of particular things.

counterclockwise  The direction around a circle opposite from that in which the hands of a clock move.

counterclockwise orientation The orientation "walking" around a figure keeping its interior to the left.

counterclockwise rotation The direction opposite that which the hands move on a nondigital clock, designated by a positive magnitude.

counterexample A specific case of a conditional for which the antecedent is true but the consequent is false. An example which shows a conjecture to be false.

counting unit The name of the particular things being tallied in a count.
Ex: I have 5 dollars. ( The count is 5, and the counting unit is dollars.)

cube A three-dimensional figure with six faces, each face being a square

cube root A real number x is the cube root of a real number y, written
, if and only if x cubed= y. ex:

cubic units Units for measuring volume.

cylinder The surface of a cylindric solid whose base is a circle.

cylindric solid The set of points between a region (its base) and its translation image in space, including the region and its image.