Respuesta :
Answer:
20
Step-by-step explanation:
if you add 20 to 20 you get a sum of 40
if you subtract 20 from 40 you get a difference of 40
Answer:
30 & 10
Step-by-step explanation:
Let be two numbers be A and B
A+B=40
A−B=20
Add two equations
We get
A+B+A−B=40+20
2A=60
A=30
as we know A put this in one of the equation
30+B=40
B=10
A=30 and B=10