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ABSOLUTE:

Fixed; not dependent on anything else. The value of 10 is absolute,
relating to unchanging numerical principles; on the other hand, the
value of 10 dollars is relative, reflecting the economy, inflation,
buying power, exchange rates with other currencies, etc.

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CALIBRATION:

The process of checking and correcting the performance of a measuring
instrument or device against a commonly accepted standard.

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CARTESIAN COORDINATE SYSTEM:

A method of specifying coordinates in relation to an x-axis, y-axis,
and z-axis. The system is named after the French mathematician and
philosopher René Descartes (1596-1650), who first described its
principles, but it was developed greatly by French mathematician and
philosopher Pierre de Fermat (1601-1665).

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COEFFICIENT:

A number that serves as a measure for some characteristic or property.
A coefficient may also be a factor against which other values are
multiplied to provide a desired result.

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COORDINATE:

A number or set of numbers used to specify the location of a point on
a line, on a surface such as aplane, or in space.

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FRAME OF REFERENCE:

The perspective of a subject in observing an object.

###
OBJECT:

Something that is perceived or observed by a subject.

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RELATIVE:

Dependent on something else for its value or for other
identifyingqualities. The fact that the United States has a
constitution is an absolute, but th efact that it was ratified in 1787
is relative: that date has meaning only within the Western calendar.

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SUBJECT:

Something (usually a person) that perceives or observes an object
and/or its behavior.

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X-AXIS:

The horizontal line of reference for points in the Cartesian
coordinatesystem.

###
Y-AXIS:

The vertical line of reference for points in the Cartesian coordinate
system.

###
Z-AXIS:

In a three-dimensional version of the Cartesian coordinate system, the
z-axis is the line of reference for points in the third dimension.
Typically the x-axisequates to "width," the y-axis to
"height," and the z-axis to
"depth"—though in factlength, width, and height
are all relative to the observer's frame of reference.

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