Past year trend
The number of questions are pretty less but more regular for an examination like JEE Mains but for JEE advanced it is like 1-2 questions occasionally.
You obviously need to know how to compute:
1. The distance between two points, point and a line.
2. Point deviding the line in the ratio of 1:k
3. Angle bisector of two line
4. Reflection in a line, foot of perpendicualr from a point is another important area.
5. Lastly the area of traingle.
Occasionally there is a question relating to finding the locus of a point which satisfies a criterion.
Some times questions from these chapter are linked with properties of triangles like properties of circumcentre, orthocentre, centroid.