Question

all of the following are coordinates on the same straight line except:
A) (0,2)
B) (3,11)
C) (5,15)
D) (7,23)
E) (x,3x+2)

Answer 1

put a line through A and B
slope = 9/3 = 3
2 = 3 (0) + b
y = 3 x + 2

now c
15 = 3*5+2 no, oh dear
then D
23 = 3*7 + 2 yes
and E
3x+2 = 3 x + 2 yes

So C is no good, invalid, evil, boil in oil

Answer 2

Thanks Damon. Now I understand the concept of it.

Answer 3

You are welcome :)