Answer:
A linear function is written in slope-intercept form as:
y = a*x + b
Where a is the slope and b is the y-intercept.
So any function of this shape, is a linear function, such that when graphed it is a straight line.
In this case, the function you wrote is:
Q: y = 1/3x + 2
Now, if the function is exactly what you wrote, then x is in the denominator:
y = 1/(3*x) + 2
Clearly, this is different than the general linear equation you can see above (here the variable is in the denominator) then in this case Q is non-linear.
If instead, the actual function Q is:
Q: y = (1/3)*x + 2
Then this is a linear equation, where the slope is 1/3 and the y-intercept is 2.