Mathematics key terms

The bearing for travelling in the opposite direction along the same line; it differs from the original bearing by $180^\circ$.

A calculation that works backwards from a final value and a percentage change to find the original value.

A quadrilateral with four equal sides.

Right angle–Hypotenuse–Side: two right-angled triangles are congruent if their hypotenuses and one other pair of corresponding sides are equal.

The right angle–hypotenuse–side test for congruence: two right-angled triangles are congruent if their hypotenuses and one corresponding pair of other sides are equal.

An angle measuring exactly $90^\circ$. It is conventionally marked by a small square at the vertex.

A triangle containing one angle of exactly $90^\circ$.

A solid with the same polygon-shaped cross-section throughout its length, with its length perpendicular to that cross-section.

A transformation that changes the position or orientation of a shape without changing its size or shape.

A value of $x$ that makes an equation true; on the graph $y=f(x)$, a real root is an $x$-coordinate where the graph meets the $$-axis.

A turn through a specified angle about a fixed centre.

The property of a shape that matches its original position after a turn of less than $360^\circ$ about a fixed centre.

Replacing a number with a nearby value stated to a chosen degree of accuracy.

The amount to which a value has been rounded, such as the nearest 1 cm, 10 kg or 0.01 second.

A marked straightedge used to draw straight lines and measure their lengths.

A smaller part of a population from which data are collected.

The number of observations or trials in a sample or experiment.

A collection of all the possible outcomes under consideration.

A table that organises possible outcomes, often with one event along the top and another down the side.

A numerical value calculated from sample data, such as a sample proportion or sample mean.

A list or other record of the members of a population from which a sample can be selected.

The natural difference between results obtained from different samples taken from the same population.

Information consisting of two side lengths and the included angle between them.

An ordinary number used to multiply a vector, changing its magnitude and possibly reversing its direction.

A vector formed by multiplying another vector by a number, such as $3\mathbf{a}$.

A statement comparing a length on a drawing or map with the corresponding real length.

A labelled line divided into sections that show the actual distances represented by lengths on a map.

A drawing in which lengths represent real lengths using a consistent scale.

A drawing in which lengths represent real lengths in a fixed proportion.

The number by which every corresponding quantity is multiplied to make a larger or smaller version.