smaller number = y
larger number = x
x - y = 69
4y = x + 3
you can solve this using substitution
x = 69 + y
(isolating one of the variables)
4y = 69 + y + 3
(substituting 69 + y for x into the other equation)
4y = 72 + y
3y = 72
y = 24
(simplify)
x - 24 = 69
x = 93
(substituting 24 into one of the original equations)