ANSWER
It varies directly
k = 6
Step-by-step explanation
We want to check if y varies directly with x.
Direct variation is represented as:
Comparing this with y = 6x, we see that it is a direct variation.
So, y varies directly with x.
This means that if y increases/decreases, x also increases/decreases.
Also, we see that the constant of variation is:
k = 6