In this video, we are going to look at compound loci. This is very similar to a regular locus, except now there are two or more conditions that have to be met.
For example:
Given line 
and a point on the line, point 
, find the compound loci of points that are 4 inches from point , and also 2 inches from line .
First, let’s look at one condition at a time, and then decide which points can satisfy both of them. So, the locus of points that are 4 inches from point will be a circle with the center located at point with a radius of 4 inches.
The locus of points 2 inches from line will be two parallel lines above and below line located exactly 2 inches from it.
We are looking for points that satisfy both conditions. Four different points can satisfy both conditions. These points are the points on the locus of point (a circle) at which the locus of line (two parallel lines) intersects the circle.
