Determine whether the variable y varies directly with x.

Question

x y
-1 -3
0 3
1 9
2 15
3 21
4 27
a) Yes, y does vary directly with x.
b) No, y does not vary directly with x.

Answer 1

To determine whether the variable y varies directly with x, we need to check if the ratio between the values of y and x remains constant. Let's calculate the ratio for each pair:

-1/-3 = 1/3
0/3 = 0
1/9 ≈ 0.111
2/15 ≈ 0.133
3/21 ≈ 0.143
4/27 ≈ 0.148

Since the ratios are not constant, we can conclude that the variable y does not vary directly with x. Therefore, the correct answer is b) No, y does not vary directly with x.