What is the formula for the sum of two whole numbers is 72. the difference is 48 what are the two numbers

X+y=72
x-y=48

Solve for one of the variables.
x=48+y

Then plug into the other equation and solve.
(48+y)+y=72
48+2y=72
2y=24
y=12

Use that answer in one of the formulas to find the other variable.
x+12=72
x=60

You can plug the answers into the original formulas to check the answers.