Let's write this question as a systems of equations to solve.
x-y=7 (the difference)
x+y=23 (the sum)
Through the process of elimination we get
2x=30
x=15.
With that value of x, we can plug it back into any of the previous equations to get the value of y.
(15)-y=7 (Solve for y)
y=8.
The two numbers are 15 and 8.
