Yes it is. In order for something to be a function, no X values can be the same, which is the case here.
<span>38 - 7r = 3(6 - 4r)
38 - 7r = 18 - 12r
-7r + 12r = 18 - 38
5r = -20
r = -4</span>
I believe its the second one because it say four times the number wich the number is the y and it is = too the number wich is y and increased going up are adding by 9. hope that helped.