Respuesta :

Hello from MrBillDoesMath

Answer:   12, 9

Discussion:

Let x be the first number and y the second number. The form the problem statement:

x + y = 21

x - y = 3


Add the two equations. This gives:

(x + x ) + ( y-y) = 21 + 3 =>

2x + 0 = 24 =>

x = 12

Since x -y =3, substituting in the value of x gives,  12 - y = 3 so y = 9


Thank you,

Mr. B

answer to equation: 18