Question

The sum of two numbers is 13. If one number is subtracted from the other, the result is -3. Find the number

Answer 1

5, 8. The two numbers are '5', and '8'. 5+8=13, while 5-8= -3.

Answer 2

let a>b

a+b=13 and b-a=-3  solve the first for b

b=13-a  and use this b in the second equation...

(13-a)-a=-3

13-2a=-3

-2a=-16

a=8, and since b=13-a, 

b=5

b+a=13, 5+8=13, 13=13

b-a=-3, 5-8=-3, -3=-3