Glossary Term Definition
two-column proof A deductive argument that contains statements and reasons
organized in two columns.
unbiased sample A sample that is selected so that it is representative of the entire
uniform tessellations Tessellations containing the same arrangement of shapes and
angles at each vertex.
union The graph of a compound inequality containing the word or; the
solution is a solution of either inequality, not necessarily both.
unit circle A circle of radius 1 unit whose center is at the origin of a
unit rate A rate with a denominator of 1.
unit vector A vector of length 1 that is parallel to the x-, y-, or z-axis.
unlike fractions Fractions whose denominators are different.
upper bound The integer greater than or equal to the greatest real zero of the
polynomial function P(x).
upper extreme The greatest number of a set of data.
upper quartile The median of the upper half of a set.
variable A letter or other symbol used to represent an unspecified
number or value.
variance The mean of the squares of the deviations from the arithmetic
vector A directed segment representing a quantity that has both
magnitude, or length, and direction.
Venn diagram A diagram that uses circles to show relationships among sets of
numbers or objects.
vertex form A quadratic function in the form y = a(x – h)2 + k, where (h, k) is
the vertex of the parabola and x = h is its axis of symmetry.
vertex of an angle The common endpoint of the rays forming the angle.
vertex of a conic section A point at which a conic section intersects its axis of symmetry.
vertex of a parabola The maximum or minimum point of a parabola.
vertex of a prism The point where three or more planes intersect.
vertical angles Opposite angles formed by the intersection of two lines. In the
figure, the vertical angles are ∠1 and ∠3, and ∠2 and ∠4.
vertical line test A test used to determine if a relation is a function.
volume The number of cubic units needed to fill the space occupied by