# Author        : Steven Miller
# Course Number : 22C:016 SCA
# Student ID    : 4784653

def slope(p1, p2) : 
    ''' Returns the slope of points p1 and p2 '''
    
    slope = None           # assume points are on a vertical line
    if float(p2[0])-float(p1[0]) != 0.0 :  # if not on a vertical line
        # compute their slope
        slope = (float(p2[1]) - float(p1[1])) / (float(p2[0]) - float(p1[0]))  
    return slope

def areCollinear(p1, p2, p3) :
    ''' Returns true if points p1, p2, and p3 are collinear'''
    
    # p1, p2, and p3 are collinear if slope(p1,p2) == slope(p2,p3)
    return slope(p1,p2) == slope(p2,p3)