c,their SUMs will not be equal. The EXPRESSIONlooks like this: if
a<b,then a+c<b+c.
See alsoSECTION IV CHARTS AND TABLES.
adjacent angle (contiguous angle)Either of two ANGLEs that share a
common side and VERTEX.
altitudeIn a figure such as a TRIANGLE, this is the DISTANCEfrom the top of the
PERPENDICULARline to the bottom where it joins the BASE, and is
usually indicated with the letter a.In a SOLIDfigure, such as a PYRAMID,
this is the perpendicular distance from the VERTEXto the base.
angle The shape formed by two lines that start at a common point, called
the VERTEX.
angle of depressionThe ANGLEformed when a HORIZONTAL LINE(the
PLANE) is joined with a descending line. The angle of depression is
equal in VALUEto the ANGLE OF ELEVATION.
angle of elevationThe ANGLEformed when a HORIZONTAL LINE(the PLANE)
is joined with an ascending line. The angle of elevation is equal in
VALUEto the ANGLE OF DEPRESSION.
antecedentThe first TERMof the two terms in a RATIO. For example, in the
ratio 3:5, the first term, 3, is the antecedent.
See alsoCONSEQUENT.
apothemThe PERPENDICULAR DISTANCEof a LINE SEGMENTthat extends
from the center of a REGULAR POLYGONto any side of the POLYGON.
arc A se gment of a curved line. For example, part of a CIRCUMFERENCE.
area The amount of surface space that is found within the lines of a two-
dimensional figure. For example, the surface space inside the lines of
aTRIANGLE, aCIRCLE, or a SQUAREis the area. Area is measured in
square units.
See alsoSECTION IV CHARTS AND TABLES.
arithmetic sequence (linear sequence)AnySEQUENCEwith a DOMAINin
the SETof NATURAL NUMBERSthat has a CONSTANT DIFFERENCE
between the numbers. This difference, when graphed, creates the
SLOPEof the numbers. For example, 1, 3, 5, 7, 9, __ is an arithmetic
sequence and the common difference is 2.
See alsoSECTION IV CHARTS AND TABLES.
arithmetic seriesASERIESin which the SUMis an ARITHMETIC SEQUENCE.GLOSSARY adjacent angle – arithmetic series
GLOSSARY adjacent angle – arithmetic series
Adjacent angle
aAltitude
Angle