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.

For the first question the answer is a, for the second c, for the third d, for the 4th b, for the 5th a