Maths Terms for 11-13 Yr Olds

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.

A portion of a curve. Often used for a portion of a circle.

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

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'.

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.

In geometry, to divide into two equal parts.

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.

Volume, i.e. a measure of three-dimensional space, applied to liquids, materials that can be poured or the space within containers. Units include cubic centimetres and litres - a

A system used to define the position of a point in two-dimensional and three-dimensional space. Two axes at right angles to each other are used to define the position of a point in a plane. The convention is to label the horizontal axis as the x-axis and the vertical axis as the y-axis. In this case, the origin is the intersection of the axes. The ordered pair of numbers (x, y) that defines the position of a point is the coordinate pair. Each of the numbers is a co-ordinate. The numbers are also known as Cartesian co-ordinates, after the French mathematician, René Descartes.

Prefix meaning one-hundredth (of)