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**ALL**

## 1 |
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## 1D. 2D, 3D:One-dimensional, two-dimensional, three-dimensional. One-dimensional: able to be identified by one co-ordinate, for example points on a line. Two-dimensional: requiring two co-ordinates for identification, for example points in a plane. Also used to describe flat geometric shapes. Three-dimensional: requiring three co-ordinates for identification, for example points in space. Also used to describe solid geometric shapes |

## A |
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## Acute Angle:An angle between zero and ninety degrees. |

## Addition:The operation to combine two numbers or quantities to form a further number or quantity, the sum or total. Addition is the inverse operation to subtraction. |

## Algebra:The part of mathematics that deals with generalised arithmetic. Letters are used to denote variables and unknown numbers and to state general properties. Example: a(x + y) = ax + ay shows a relationship that is true for any numbers a, x and y. Adjective: algebraic. See also equation, formula, identity and expression. |

## Alternate Angles:
Where two straight lines are cut by a third, as in the diagrams,
the angles Where the two straight lines are parallel, alternate angles are equal. |

## Analogue Clock:A clock usually with 12 equal divisions labelled 1 to 12 to represent hours. Each twelfth is subdivided into five equal parts providing sixty minor divisions to represent minutes. The clock has two hands that rotate about the centre. The minute hand completes one revolution in one hour whilst the hour hand completes one revolution in 12 hours. |

## Angle:Where two line segments meet at a point, this term describes the measure of rotation (normally clockwise) from one of the line segments to the other. In this way, a right angle measures 90 degrees, an acute angle is between 0 and 90 degrees, an obtuse angle is between 90 and 180 degrees and a reflex angle is greater than 180 degrees. |

## Approximate:A number or result that is not exact. In a practical situation an approximation is sufficiently close to the actual number for it to be useful. Verb: approximate. Adverb: approximately. When two values are approximately equal, the first symbol below is used instead of the normal = sign. If all that's known is the order of magnitude, the second symbol below is used.
For example, there are approximately 365 days in a year (there are 365.25 to be exact, making each fourth year a leap year with 366 days), and the mass of the Sun in kg is known to be roughly 2 with 24 zeroes after it. |

## Arc:A portion of a curve. Often used for a portion of a circle. |

## Area:A measure of surface. Area is usually measured in square units e.g. square metres. |

## Arithmetic Sequence:A sequence of numbers in which terms are generated by adding or subtracting a constant amount to the preceding term. Examples: 3, 11, 19, 27, 35, . where 8 is added; 4, -1, -6, -11, . where 5 is subtracted. |

## Array:An ordered collection of counters, numbers etc. in rows and columns. |

## Average:See 'meanâ€™. Compare with 'mode' and 'median'. |

## Axis:A fixed, reference line along which or from which distances or angles are measured, and shapes are translated. For axis of symmetry, see 'reflection symmetry'. |

## B |
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## Bar Chart:A format for representing statistical information. Bars, of equal width, represent frequencies and the lengths of the bars are proportional to the frequencies. Sometimes called bar graph. |

## Bar Line Chart:Similar to a bar chart, the width of bars is reduced so that they appear as lines. The lengths of the bar lines are proportional to the frequencies. Sometimes called bar line graph. |

## Bearing:The direction of a line specified by the angle it makes with a North-South line. The angle is measured in degrees from North in a clockwise direction. Bearings are usually given in a three figure format. |

## Bisect:In geometry, to divide into two equal parts. |

## Bisector:A point, line or plane that divides (a line, an angle or a solid shape) into two equal parts. A perpendicular bisector is a line at right angles to a line segment that divides it into two equal parts. |

## Box Plot:A diagram to represent a set of ranked numerical data. A box represents the interquartile range. Lines from the points representing the maximum and minimum values to the box are sometimes referred to as whiskers. The median is marked on the box by a line. |