The sum of two numbers is 7. If one number is subtracted from the other, the result is -3. Find the numbers

Question

I don't understand how to answer this

Answer 1

let's call the numbers x and y

x + y = 7

x - y = -3 or y - x = -3 (We consider two cases because subtraction is not commutative like addition)

 

x+y=7

x-y=-3

 

x=2 and y=5

 

x+y=7

y-x=-3

 

y=2 and x = 5