Question 1
The number of lines passing through five points such that no three of them are collinear is
a) 10
b) 5
c) 20
d) 8
Three or more points are said to be collinear if they lie on a single straight line.
Let A, B, C, D and E be five points such that no three of them are collinear.
∴ Lines passing through these five points are AB, BC, CD, DE, EA, BE, BD, CE, AC and AD.
Hence, the number of lines are 10.