Find two numbers whose sum is 29 and whose difference is 15

The two numbers are 22 and 7.

22 + 7 = 29

22 - 7 = 15

here is how we can find these numbers;

let a and b are two numbers

a + b = 29

a - b = 15

a = 15 + b

now put this value of a in any of the equation

a + b = 29

15 + b + b = 29

15 + 2b = 29

2b = 29 - 15

2b = 14

b = 7

now put the value of b to find the value of a;

a = 15 + b = 15 + 7 = 22

a = 22