Please can someone help with this. Not sure where I am going wrong? Find the equation of the line joining points (1,9) and (3,1)

m=y2-y1/x2-1= 1-9/3-1=-8/2=-4

m= -4, a = 3, b= 1

y-b= m(x-a)
y-1=-4(x-3)
y-1=-4x+12
y= -4x + 11

Aresearch study is done to find the average age of all u.s. factory workers. the researchers asked every factory worker in ohio what their birth year is. this research is an example of a census survey convenience sample simple random sample