Mathematical "O" Words
cone whose axis is not perpendicular to its base.
A 3-dimensional figure in which the plane of the base(s) is not perpendicular
to its axis or to the planes of its lateral surfaces.
line that is neither horizontal nor vertical.
An angle whose measure is between 90° and 180°. Remember
a 90° angle is called a right angle not an obtuse angle, and a
180° angle is called a straight angle not an obtuse angle.
A triangle with an obtuse angle.
A polyhedron with eight faces.
A node which is the endpoint of an odd number of arcs in a network.
A space in which all points are collinear. Basically a single line.
A justified conclusion of a conditional requiring a single definition,
theorem, or postulate.
A sentence with variables that can be true or false, depending on what
is substituted for the variables.
EX: x + 4 =16 is only
true for x=12.
For all real numbers n: -(-n) = n.
When a given number is added to its opposite you always get ZERO. The
opposite of a number n is denoted -n. Also called additive
EX: 6 is the opposite
of -6 because when you add them 6+-6=0.
pair of faces of a polyhedron whose planes are parallel to each other.
which are congruent and have opposite orientation.
Ray AB and Ray AC are opposite rays if and only if A is between B and
A pair of numbers ( x, y ) in which x is the first coordinate and y is
the second coordinate.
pair description of a vector
The description of a vector as the ordered pair
(a,b) where a is the horizontal component and b is the vertical component.
Rules for evaluating an expression: work first within parentheses, then
calculate all exponents, then do multiplication and division together
as they appear in the problem from left to right; then do addition and
subtraction as they appear from left to right.
NOTE: Many math teachers
teach the saying,
"Please Excuse My Dear
Aunt Sally" or PEMDAS. Each capital
letter stands for an operation.
P~parentheses or all grouping symbols
M&D~ multiplication and division from left to right
A&S~ addition and subtraction from left to right
The order of the designation of the vertices of a polygon, either clockwise
EX: figure ABCDEFG above has a clockwise orientation.
point where the x and y axes intersect denoted by ( 0, 0 ).
unit of weight in the U.S. system of measurement equal to 1/16 of a pound.
1 ounce 29.574
Figures which have some interior points in common.
Triangles that have interior points in common.