Let's start by assigning variables for each of the numbers. Let the first one be x, the second one be y.
x + y = 36
x = 3y - 4
Now we solve using substitution.
3y - 4 + y = 36
This simplifies into:
4y = 32
y = 8.
Now we need to solve for x.
36 - 8 = 28 (because x + y = 36)
x = 28