# Math Dictionary o

This page is about Math Dictionary o.**O**

**Oblique line and a plane:**A line and a plane that are neither parallel nor perpendicular.

**Obtuse angle**An angle whose measure is greater than 90 degrees and less than 180 degrees.

**Obtuse triangle:**A triangle having one obtuse angle.

**Octagon:**A polygon with 8 sides.

**Octahedron:**A polyhedron having eight faces. A regular octahedron is one of the five Platonic solids and has eight equilateral triangles as faces.

**Odd number :**Any integer that CANNOT be divided exactly by 2.

**Odometer :**An instrument (usually on the instrument panel of a car) that records distance traveled.

(A speedometer measures the current speed)

**Ogive :**It is also known as Frequency curve. It is used to find median of the data.

**One-to-one function:**A function where the inverse is also a function.

**Operator :**An Operator is a symbol (such as +, ×, etc) that represents an operation (i.e. you want to do something with the values).

**Opposite rays:**Two collinear rays whose intersection is exactly one point.

**Opposite side in a right triangle:**The side across from an angle. In a right triangle the hypotenuse is opposite the right angle and each leg is opposite one of the acute angles

**Opposite transformation:**A transformation of the plane that changes the orientation of a figure.

**Order of Operations :**The rules of which calculation comes first in an expression(PEDMAS).

**Ordered pair:**Two numbers that are used to identify the position of a point in a plane. The two numbers are called coordinates and are represented by (x, y).

**Ordered triple:**Three numbers that are used to identify the position of a point in space. The three numbers are called coordinates and are represented by (x, y, z).

**Ordinal Number :**A number that tells the position of something in a list.

**Ordinate:**The vertical coordinate of a two-dimensional rectangular coordinate system; usually denoted by y.

**Orientation:**The arrangement of the points, relative to one another, after a transformation; the reference made to the direction traversed (clockwise or counterclockwise) when traveling around a geometric figure.

**Origin :**The point in the Cartesian coordinate plane at which the horizontal and vertical axes intersect, designated by the ordered pair (0,0).

**Orthocenter :**The point of concurrence of the three altitudes of a triangle.

**Math dictionary o**

From math dictionary o to math dictionary

Home

From math dictionary o to math dictionary

Home