Answer:
99 and - 12
Explanation:
let x and y be the 2 numbers, then
x + y = 87 → (1)
x - y = - 111 → (2)
Adding the 2 equations term by term eliminates the y- term
2x = - 24 ( divide both sides by 2 )
x = - 12
Substitute x = - 12 into (1)
- 12 + y = 87 ( add 12 to both sides )
y = 99
The 2 numbers are 99 and - 12