Maths Terms for 11-13 Yr Olds

A measure of the slope of a line. On a coordinate plane, the gradient of the line through the points (x1, y1) and (x2, y2) is defined as (y2 - y1) / (x2 - x1).

The gradient may be positive, negative or zero depending on the values of the co-ordinates. In a straight line graph of the form y = mx+c, m represents the gradient.

Symbol: g. The unit of mass equal to one thousandth of a kilogram.

A diagram showing a relationship between variables. Adjective: graphical. A graph showing information that isn't continuous is often called a 'chart' instead.

A polygon with seven sides or edges.

A polygon with six sides or edges. Adjective: hexagonal, having the form of a hexagon.

The common factor of two or more numbers which has the highest value. Example: 16 has factors 1, 2, 4, 8, 16. 24 has factors 1, 2, 3, 4, 6, 8, 12, 24.

56 has factors 1, 2, 4, 7, 8, 14, 28, 56. The common factors of 16, 24 and 56 are 1, 2, 4 and 8. Their highest common factor is 8.

A particular form of representation of grouped data. Segments along the x axis are proportional to the class interval. Rectangles are drawn with the line segments as bases. The area of the rectangle is proportional to the frequency in the class. Where the class intervals are not equal, the height of each rectangle is called the frequency density of the class.

Parallel to the horizon. Also in the direction of the x axis in a Cartesian co-ordinate system.

A polyhedron with 20 faces. In a regular icosahedron all faces are equilateral triangles.

An equation that holds for all values of the variables, as opposed to a normal equation which has only one or two fixed solutions. An equals sign with three horizontal lines rather than two is sometimes used when writing an identity. For example the identity below is true no matter what the values of a and b are.