S

**scalar: a quantity that has size but no direction.**

**scalene triangle: a triangle with three unequal sides.**

**secant: a line that intersects a circle or a curve in
two places.**

**secant: the reciprocal of the cosine.**

**second: the unit of measure of an angle that is 1/60 of
a minute.**

**sector: a region bounded by two radii of a circle and
the arc whose endpoints lie on those **

** radii.**

**segment: the union of a point, A, and a point,
B, and all the points between them.**

**series: the sum of a sequence.**

**set: a well defined group of objects.**

**similar: two polygons are similar if their corresponding
sides are proportional.**

**simoultaneous equations: a group of equations that are
all true at the same time.**

**sine: in a right triangle, the length of a side opposite
an angle divided by the length of the **

**hypotenuse of the triangle.**

**skew: two lines that are not in the same plane.**

**slope: the slope of a line is the change in the
vertical coordinates/the change in the **

** horizontal
coordinates of any two points on the line.**

**solid: a three dimensional object that completely
encloses a volume of space.**

**sphere: the set of all points in space that are a fixed
distance from a given point.**

**square: a quadrilateral with four equal sides and
four 90 degree angles.**

**square root: of a number, x, is the number
that, when multiplied by itself gives the **

** number,
x.**

**subset: A set, B, is a subset of another
set, A, if every element in B is also an element of **

* A*.

**sum: the result of adding.**

**supplementary: two angles are supplementary if their sum
is 180 degrees.**

**symmetric: two points are symmetric with respect
to a third point if the segments joining **

** them
to the third point are equal. Two points are symmetric with
respect to a **

** line
if the line is the perpendicular bisector of the segment joining the points.**