Domain is the set of possible values for x. It consists of EVERY
NUMBER that X can represent.
Range is the set of possible values for y. It consists of EVERY
NUMBER that Y can represent.
REMEMBER
D comes before R
and X comes before Y
This closed circle tells me that my domain
exists at -6 and my range exists at -3.
When a line segment has a closed
circle, that number is included in
your domain and range.
When a line segment has an open
circle, that number is not included
in your domain and range.
This open circle tells me that my
domain gets infinitely close to 7 but
does not exist at 7 and my range gets
infinitely close to 2 but does not exist
at 2.

Closed circles are represented by brackets [ ] or by the
inequalities ≤ and ≥.

Open circles are represented by parenthesis ( ) or by the
inequalities < and >.


DOMAIN [-6,7) or -6 ≤ x < 7
RANGE [-3,2) or -3 ≤ x < 2
x = -7, 2, 6, 7
-6 ≤ x ‹ 7
[-6,7)
y = -4, 0,3
-4 ≤ y ‹ ∞
[-4, ∞)
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