1. Which of the following points are non-collinear? => M , C , E or L , R , N or R , C , T
or L , C , S..
Question: Which of the following points are non-collinear?
Understanding the Problem
- Do you know what non-collinear? (I don’t)
- Do you know the function of diagram? (I don’t)
- Do you know how many lines are collinear? (I don’t)
Planning a Solution
- If collinear is same as straight line, non- collinear is not straight line.
- So that, we know line that is straight or not.
- It means that, we can know where the non-collinear line in the diagram.
Finding the Answer

2. Method A - Making diagram
M
C diagram show MCE is straight line, so it is collinear
E
L
C diagram show LCS is straight line, so it is collinear
S
R
C diagram show RCT is straight line, so it is collinear
T

3. N
R diagram show RLN is not straight line,
So line LRN is non-collinear
L
Problem extension
The diagrams show four lines that are LRN, MCE, RCT and LCS. We must know the
pattern among the lines. The target is to find the non-collinear from the diagram.
When we use diagram method to separate the four lines, we can see the diffrences
among the lines. Finally we know that line LRN is non-collinear.