radius of a
circle or sphere A
segment connecting the center of a circle or a sphere with a point on that
circle or sphere, also, the length of that segment. Plural is radii.
A quantity whose unit contains the word " per " or "
for each " or some synonym.
per hour, beats per minute, candy bars for each child
rate used in multiplication .
Model for Division If
a and b are quantities with different units,
then a/b is the amount of quantity a per
Factor Model for Multiplication
When a rate
is multiplied by another quantity, the unit of the product is the ( product
) of units multiplied like fractions. The product has meaning whenever
its units have meaning.
Ex: You can see that the following rate multiplication changes
6 days into its equivalent number of seconds:
unit of measurement in a rate.
of two quantities with the same units.
Comparison Model for Division
If a and b are quantities with the same units, then a/b compares
a to b.
In similar figures, the ratio of a distance or length in an image to the
corresponding distance or length in a preimage.
Ex: When comparing
the following small right triangle to its similar large right triangle,
we see a ratio of similitude of 0.5.
number that can be written as a simple fraction. These numbers can also
be written as terminating or repeating decimals.
A part of a line which begins at some point and goes on forever in a particular
direction. The ray with endpoint A containing B is denoted
number that can be written as a decimal. The set of Real numbers is made
up of all rational numbers as well as all irrational numbers.
A number which, when multiplied by a given number, yields the product
1. Also called multiplicative inverse. An example of
this is the numbers 2 and 1/2. When multiplied, they yield 2/2, which
A quadrilateral with four right angles.
arrangement of objects into rows and columns.
A box. The union of a box and its interior.
line over which a preimage is reflected. Also called mirror line
or line of reflection.
||Here we see
the classic heart shape. It has a mirror line drawn vertically through
plane over which a preimage is reflected. Also called mirror.
A transformation in which each point is mapped onto its reflection image
over a line or plane.
The image of a figure reflected over a line.
The union of a polygon or circle with its interior is known as a region.
A convex polygon whose sides all have the same length and angles all have
the same measure.
A convex polyhedron whose faces are all congruent regular polygons and
the same number of edges intersect at each of its vertices. There are
only five of these that can be constructed out of a single polygon shape.
(four faces each an equilateral triangle)
- Cube or Hexahedron
(six faces each a square)
(eight faces each an equilateral triangle)
(twenty faces each an equilateral triangle)
(twelve faces each a regular pentagon)
A right prism whose base is a regular polygon.
A right pyramid whose base is a regular polygon and whose lateral faces
are congruent isosceles triangles.
||Here we see
a right pyramid with a square base. It would be classified as a regular
Facts Property of Multiplication and Division
If xy = P, then P/x = y and P/y = x. Or a numerical
If you know that 4x6=24, then the related facts are 24/4=6 and
Addition Model for Multiplication
If n is a positive integer, then nx = x + x + . . .
+ x. ( n addends)
The digits which
repeat forever in an infinitely repeating decimal.
"16" is the repetend in this example.
A turn of 360°. Also called full turn.
A quadrilateral with all sides of the same length.
angle whose measure is 90°. A right angle will always be drawn with a
small square at its vertex. This removes all doubt that it is a 90 degree
angle. If you don't see the square you cannot assume that it is
a right angle.
method for finding the center of a circle that involves constructing two
inscribed right triangles. The intersection of their hypotenuses is the
A cone whose axis is perpendicular to the plane of the circular base.
A cylinder formed when the two circular bases are directly across from
each other. The walls of a right cylinder are perpendicular to both bases.
A right prism is formed when two polygonal bases are placed right across
from each other. The walls of a right prism are perpendicular to both
A pyramid whose base is a regular polygon and in which the segment connecting
its vertex to the center of its base is perpendicular to the plane of
||In a right
pyramid, the vertex will always be directly above the center of the
regular polygon base.
triangle with a right angle.
||In this example
we see a right triangle with legs a and b and
hypotenuse c. We also see an equation known as the Pythagorean
Theorem which is true for every right triangle.
A transformation in which every point of the preimage is rotated by a
given angle about a point (in two dimensions) or a line (in three dimensions).
A figure which when rotated less than 360 degrees will lie on top of itself.
an estimate that is smaller than the exact value.
rounded down to the preceding whole number is 13.
to the nearest Making
an estimate to a particular decimal place by either rounding up or rounding
down depending on which estimate is closest to the exact value.
rounded to the nearest whole number is 14.
Making an estimate that is bigger than the exact value.
Ex: 13.74 rounded
up to the next tenth is 13.8.
tournament in which each competitor plays each other exactly once.
A horizontal line of objects in a rectangular array.
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