Question 318939
the difference of two numbers is 6. Their sum is 30. Find the two numbers.
please show all work 

Let x and y be the two numbers.  Then we have:

1.) x - y = 6 and
2.) x + y = 30

From 1.) we have x = y + 6.  Substituting y + 6 for x in 2.) we have:

(y+6) + y = 30
2y = 24
y = 12

Since x = y + 6 we have x = 12 + 6 = 18