How many straight lines can be drawn between five points (A, B, C, D, and E), no three of which are colinear?
Attempt: Given 5 points, a line consist always of 2 points. Thus the total number of straight lines that can be drawn between 5 points is 5_C_2 = 10. Is this correct? Thank you.
Your answer is correct; you just ought to note that, since no three are collinear, no two pairs of points may yield the same line.