Hello from MrBillDoesMath!
Answer:
Not equation exists as the points o not lie on a line
Discussion:
Compute slope for first and second points:
m = (diff of y)/(diff of x) = (150-100)/(2-1) = 50/1 = 50
Slope for second and third points:
m = (250 -150)/(3-2) = 100/1 = 100
As 50 is not equal to 100 the points do not lie on a single line.
Regards,
MrB