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The sum of two numbers is 30 in the difference is 12 find The two numbers

User Follyroof
by
6.6k points

2 Answers

2 votes

Answer:

30-9=21

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.

User Joooeey
by
7.8k points
5 votes
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.


User Andrew Koster
by
7.7k points