Find two numbers with a sum of 15 and a difference of 4?

Answer 1

Let us consider x and y as the two numbers

x + y = 15

x - y = 4

Adding the two above equations

2x = 19

x = 19/2 = 9.5

Take the first equation:

x + y = 15

y = 15 - x = 15 - 9.5 = 5.5

The two numbers are 9.5 and 5.5

Answer 2

12