Respuesta :

let's call the numbers x and y:

their sum is:

x+y=30

and their difference is x-y=12.

from the first equation: x=30-y

and we insert this into the second equation:
30-y-y=12.

we calculate:

30-2y=12

30-12=2y
18=2y
9=y

so the first number is 9 and the second is 30-9=21.


jadranm25

Answer:

30-9=21

Step-by-step explanation:

x+y=30

difference is x-y=12.

first equation: x=30-y

insert this to the second equation:

30-y-y=12.

30-y=12

30-12=2y

18=2y

9=y

first number is 9 the second is 30-9=21.