## Glossary

Absolute value:
(of an integer) the size or magnitude of the number without regard to the sign
Acute triangle:
a triangle with each angle less than 90; also called an acute-angled triangle
squares in which the sum of the numbers in each row, column, or diagonal is the same
pairs of angles sharing a common side and a common vertex
Algebra:
the branch of mathematics that uses variables to study the relationship between numbers
Algebraic expression:
a combination of variables, numbers, and arithmetic operations; also called a variable expression
Algorithm:
a set of steps for finding the answer to a problem
Apothem:
the perpendicular distance from the centre of a regular polygon to a side
Arc:
the part of a circle between any two points on the circle
Axis of symmetry:
a line about which a symmetrical three-dimensional object can be rotated so that its turn image matches its original position more than once in a full turn
Base (of a parallelogram):
any side of a parallelogram
Base (of a polyhedron):
the face or pair of faces from which the height of the polyhedron is measured
Bases (of a trapezoid):
the parallel sides of a trapezoid; sometimes called and because they are of different lengths
Box and whisker plot:
a graph that illustrates the spread of data
Cancelling:
(in multiplication) the process of dividing a numerator and a denominator by a common factor
Capture-recapture:
a sampling method used to estimate the number of wild animals in a region
Cartesian coordinate system:
a way of defining the position of a point in two-dimensional space
Central angle:
the angle formed by a pair of radii
Central tendency (measure of):
the statistic that gives an averagemedian, mean, mode
Chance:
the probability of an event happening, usually expressed as a percent
Chord:
a line segment joining two points on a circle
Circle:
a set of all points in a plane that are the same distance from a fixed point called the centre
Circumference:
the distance around a circle
Clusters:
values grouped closely together in a set of data
Commission:
the pay an employee earns based on a percentage of the sales made by the employee
Complex fraction:
a fraction which has a fraction in the numerator and/or in the denominator
Composite (figure):
a figure made up of two or more shapes
Composite shape:
an object composed of a combination of two or more basic shapes
Compound interest:
the interest earned (charged) on an amount of money and added to the principal to earn (charge) more interest in the following year
Concave (polyhedron):
a polyhedron in which some of the flat surfaces slope inwards
Conditional equation:
an equation that is only true for certain values of the variable
Convex (polyhedron):
a polyhedron in which all the flat surfaces slope outwards
Cross section:
a two-dimensional figure that is the intersection of a three-dimensional solid and a plane
Dart:
a concave trapezium with two sets of adjacent sides congruent; also called an arrowhead or a deltoid
Degree (of a vertex):
the number of edges that meet the vertex
Diagonal:
a line segment joining any two vertices of a polygon not already joined
Diameter:
a chord through the centre of a circle
Dilatation:
a kind of transformation in which the image is an enlargement or a reduction of the original
Discount:
the amount by which the regular price is reduced Interest: the amount paid for the use of money
Distribution (measures of):
the statistics that give the spreadextremes, range, quartiles, interquartile range, clusters, and gaps
Dividend:
the number which is to be divided
Divisor:
the number by which the dividend is to be divided
Edge:
a line segment formed by the intersection of two faces
Even vertex (of a network):
a vertex having an even number of edges connected to it
Face:
one of the flat surfaces of a polyhedron
Factors:
in a mathematical statement, the numbers being multiplied
First-hand (primary) data:
data gathered directly
Formula:
an equation that shows how one quantity is related to one or more other quantities
Gaps:
spaces between values in a set of data
Height (of a parallelogram):
in a parallelogram, the perpendicular distance from the base to the opposite side
Height (of a polyhedron):
the vertical distance from a vertex to the base
Height (of a trapezoid):
the perpendicular distance between the bases of a trapezoid
Inscribed angle:
an angle drawn inside a circle so that the vertex of the angle is on the circle and the arms of the angle are chords of the circle
Inscribed:
a figure drawn inside a circle or other figure, with all the points of the inner figure touching the outer figure
Interquartile range:
the difference between the upper quartile and lower quartile
Inverse operations:
operations that undo each other
Isosceles trapezoid:
a trapezoid with the non-parallel sides congruent
Kite:
a convex trapezium with two sets of adjacent sides congruent
Line plot:
a graph used to organize and display data; also called a data plot
Lower extreme:
the least value in the set of data
Lower quartile:
the middle value (or average of the two middle values) in the set of values less than the median
Mean:
the arithmetic average of a set of data
Median:
the middle value (or the average of the middle two values) in a set of data arranged in ascending order
Mode:
the value that occurs most frequently in a set of data
Monte-Carlo method:
a technique where events are modelled using probability tools such as coins, dice, and dials, or using a computer to generate random numbers -- These models are called simulations.
Multiplicative inverses:
two numbers whose product is 1; also called reciprocals
Net:
a two-dimensional pattern that can be folded into a three-dimensional shape
Network:
a figure consisting of edges and vertices; sometimes called a graph
Obtuse triangle:
a triangle with an angle greater than 90; also called an obtuse-angled triangle
Odd vertex (of a network):
a vertex having an odd number of edges connected to it
Odds (against):
a comparison of the unfavourable outcomes to the favourable outcomes
Odds (in favour):
a comparison of the favourable outcomes to the unfavourable outcomes
Opposite angles (in a parallelogram):
Origin:
on a graph, the point where the x-axis and y-axis meet
Outliers:
values in a set of data that are more than 1.5 times the interquartile range above the upper quartile or below the lower quartile
Parallelogram:
a quadrilateral with two pairs of parallel sides
Percent:
a ratio having 100 as its second term
Perfect square:
a number that has a counting number (natural number) as its square root
Perimeter:
the distance around a figure
Plane of symmetry:
a plane (flat surface) which divides a symmetrical three-dimensional figure into two identical halves
Polygon:
a simple closed figure with straight sides
Polyhedron:
(plural: polyhedra) a three-dimensional shape which has only flat surfaces
Population:
in statistics, the set of people, animals, or things being studied
Power of ten:
power with a base of ten
Principal:
money which is invested or borrowed
Problem:
a task for which the method of finding the answer (as well as the answer) is not immediately known
Product:
the result in multiplication
Proportions:
equations that show two ratios are equivalent
Pythagorean relation:
the relationship that shows that in a right triangle, the sum of the squares of the legs is equal to the square of the hypotenuse; a2 + b2 = c2
Pythagorean triple:
three numbers whose sum of the squares of the two smaller numbers equals the square of the third number
one of the four regions formed by the axes on a graph
Quotient:
the number resulting from division
a line segment from the centre of a circle to any point on the circle
Range:
the difference between the upper extreme and lower extreme in a set of data
Rate:
a comparison of quantities measured in different units
Ratio:
a comparison of quantities measured in the same unit
Rectangle:
a parallelogram with a right angle
Regular polygon:
a polygon with congruent sides and congruent angles
Regular polyhedron:
a polyhedron in which all the faces are identical regular polygons and in which the same number of faces and the same number of edges meet at each vertex
Relative frequency:
the ratio of the number of times something has occurred to the number of times it could occur
Rhombus:
a parallelogram with four congruent sides
Right triangle:
a triangle with an angle of 90; also called a right-angled triangle
Sample:
the part of the population that is surveyed or tested
Scale drawing:
a drawing used to accurately picture a person, animal, or thing that is too large or too small to be drawn actual size
Scale factor:
in a drawing, the ratio of the drawn length to the actual length expressed as a single number
Scale model:
a likeness of an object that has the same proportions as the object
Scientific notation:
a way of expressing a number as the product of a power of ten and a number between 1 and 10
Second-hand (secondary) data:
data obtained from others
Sector:
the region in a circle bounded by a pair of radii and an arc
Semi-regular polyhedron:
a polyhedron in which the faces consist of at least two different types of regular polygons combined in the same way around each vertex; for example, the shapes of a soccer ball
Sequence:
a set of numbers or pictures that is ordered according to some rule or formula
Shell:
a three-dimensional model in which the interior is empty
Skeleton:
a three-dimensional model showing only the edges and vertices of a three-dimensional shape
Solid:
a three-dimensional model in which the interior is filled
Solution (of an equation):
the value of the variable that makes the equation true
a computer-generated arrangement of data in rows and columns
Square root:
a number which, when multiplied by itself, results in the given number
Square:
a parallelogram with four congruent sides and a right angle
Standard form:
the usual form of a number
Subtraction magic squares:
squares in which the sum of the two end numbers (in any row, column, or diagonal), minus the centre number, is the same
Supplementary (angles):
two angles having a sum of 180
Symmetry:
the property that makes a figure look balanced
Tangram:
an ancient Chinese puzzle that has seven geometric shapes called tans (two large triangles, one medium triangle, two small triangles, a square, and a parallelogram)
Technology:
the application of tools, materials, and processes to problem solving; more specifically, devices and systems used in processing, transferring, storing, and communicating information through electronic media
Term:
each number or item in a sequence -- The first number in a sequence is called the first term, the second number is called the second term, and so on.
Tessellation:
an arrangement of congruent figures that covers a surface without gaps or overlapping
Theoretical probability (of an event):
the ratio of the number of favourable outcomes (what you want to happen) to the number of possible outcomes (what could happen)
Trapezium:
a quadrilateral without any parallel sides
Trapezoid:
a quadrilateral with exactly one pair of parallel sides
Traversable:
a network that has a path that travels along every edge exactly once
Upper extreme:
the greatest value in a set of data
Upper quartile:
the middle value (or average of the two middle values) in the set of values greater than the median
Variable:
a quantity, represented by a symbol that may have many values
Vertex:
(plural: vertices) a point in a polyhedron where three or more edges meet
Volume:
the amount of space an object occupies
Windchill equivalent temperature:
a temperature which indicates how cold a wind makes the air feel