Question

The sum of two numers is 52 . The difference of the two numbers is 38 . What are the two numbers? Write the two numbers separated by a comma.

Answer 1

Let the first number be 'x' and the second number is 'y'

Equation 1: x + y = 52
Equation 2: x - y = 38

Rearranging equation 2 to make either x or y the subject
x = 38 + y

Substituting x = 38 + y into equation 1

x + y = 52
(38+y) + y = 52
38 + 2y = 52
2y = 52 - 38
2y = 14
y = 7

Substitute y = 7 into either equation 1 or equation 2 to find x

x + y = 52
x + 7 = 52
x = 52 - 7
x = 45

x = 45
y = 7