Answer: x = 4, y = 8
Explanation:
Let the two numbers be x and y
sum of the two numbers will be
x + y = 12 ------------------------------1
Difference of the two numbers
x - y = -4 ----------------------------- 2
Now, to find the two numbers , we solve equation 1 & 2 together
x + y = 12
x - y = -4
we now add the two equations to eliminate y
2x = 8
x = 4. Now to find the value of y, we substitute for x in any of the equation above
x + y = 12
4 + y = 12
y = 12 - 4
y = 8