10-6

1
10-6 10-8 Locus, Loci, and Locus construction
Locus is a set of points that satisfy a condition
or a set of conditions. Loci is plural.
Key words In a plane, and in space They may
give you different pictures (circle v sphere
parallel lines v cylinders perpendicular line v
perpendicular planes) and others.
2
Standard example. Lets find the set of all
points on a plane from point A that are BC away.
B
C
A
3
Set of all points in a plane 2 cm away from a
line.
How would it change if it was a line segment?
4
Groups of 4 (I pick them) In your own notes, you
will try to describe the loci, see what you can
come up with.
5
Draw two points labeled A and B. Find all the
points on a plane equidistant from both A and B.
Can you tell me whats special about it?
Draw two lines m and n that intersect at point P.
Find all the points on a plane that are
equidistant from line m and n.
Draw 3 non collinear points A, B, C. Find all
points on a plane that are equidistant from A, B,
and C.
Draw line l. Find all the points in space that
are 1 cm from line l.
Given a circle Q and line m. What are all the
possible locus points and draw what they would
look like.
Discuss in context of space\plane
6

• T - HW 25  Pg 404 1, 317, 19, 20, 22, 24 Pg
  407 14