Final answer:
The general solution of the given differential equation z'' - 6z' = 0 is z(t) = a + bt, where a and b are constants.
Step-by-step explanation:
The given differential equation is z'' - 6z' = 0.
To find the general solution, we can rewrite the equation in terms of the derivative notation: r^2 - 6r = 0, where r represents dz/dt.
Factoring out r, we have r(r - 6) = 0. Therefore, r = 0 or r = 6.
The general solution is z(t) = a + bt, where a and b are constants.