Mira picked two numbers from a bowl. the difference of the two numbers was 4, and the sum of one-half of
each number was 18. the system that
represents mira's numbers is below x-y=4 1/2x+1/2y=18

Let the two numbers be x and y.

The difference between the numbers is 4. Therefore
x - y = 4             (1)

The sum of one-half of each number is 18, therefore
x/2 + y/ 2 = 18
x + y = 36          (2)

Add equations (1) and (2).
(x - y) + (x + y) = 4 + 36
2x = 40
x = 20
From (2), obtain
y = 36 - x = 36 - 20 = 16.

The two numbers are 16 and 20.