Term

Definition

table 
a way to display data in rows and columns 
tan 
trig ratio tan θ = ^{opp}/_{adj }

tangent 
a line that touches a circle or curve at only one point 
taxable income 
income that tax is calculated on. Gross income subtracted by allowable deductions 
term 
the name of a part of an algebraic expression. 2x + 4 has two terms, 2x and 4 
terminating decimal 
a decimal that can be expressed exactly to a finite number of decimal places 
tessellation 
a repeating pattern of figures that completely covers a plane without gaps or overlap 
tetrahedron 
four sided solid such as a triangular pyramid

theta 
Greek letter often used to represent unknown angles. Capital theta, Θ is rarely used, but small theta, θ is used commonly in maths 
tonne 
a metric unit of weight. One tonne equals 1000 kg 
torus 
a 3d shape like the shape of a doughnut

total 
sum 
transformation 
when a change is made to a shape to move or make a new shape:translate, reflect, rotate, enlarge 
translation 
transformation of sliding a shape 
transpose 
to replace 
transversal 
a line that crosses two or more lines 
trapeziod 
a quadrilateral where no sides are equal 
trapeziodal rule 
used to find an approximate area under a curve A ≈ ^{h}/_{2}{f(a) + f(b) + 2(sum of the function of all the other ordinates)} 
trapezium 
quadrilateral with one pair of opposite sides parallel . The area of a trapezium is given by: A = ^{h}/_{2}(a + b), where a and b are the two parallel sides and h is the perpendicular distance between them. If the two nonparallel sides are equal, then it is an isosceles trapezium

travel graph 
a straight line graph used to show distance travelled. Time is displayed on the horizontal axis, and distance from a certain point on the vertical axis. A horizontal line on a travel graph means that they are stopped, not travelling. 
tree diagram 
a diagram to display the probabilities and outcomes of an event

trial and error 
guess and check method. Basically you make a guess at an answer, check to see if it is right, then try again until you get the correct answer 
triangle 
3 sided figure. Area = ^{1}/_{2}bh

triangle inequality 
the lenghts of two sides of the triangle must sum to be greater than the third side. 
triangular numbers 
1, 3, 6, 10, 15, 21, 28, 36, …. 
triangular prism 
prism with a triangular base, looking like a tent. It has five faces, six vertices and 9 edges

triangular pyramid 
pyramid with a triangular base. It has four faces, four vertices and six edges

trig 
abbreviated form of trigonometry 
trigonometry 
area of study dealing with relationships between angles and side lengths 
trinomial 
any algebraic expression with three terms 
truncated 
to be shortened or ‘chopped off’. A truncated decimal is a rounded decimal. The diagram shows a truncated cone.

turning point 
the point of a curve where the tangent to the curve at that point is horizontal. Turning points are found by setting ^{dy}/_{dx} = 0

twice 
to multiply by two, to double 