The Sum Of Two Numbers Is 69 And Their Difference Is 9

The problem given says that 2 unknown numbers are given, whose sum is equal to 69 and the difference is 9. Let's find the two numbers :

When we add the two numbers :
X + Y = 69

The difference of two numbers :
X - Y = 9

Solution :

If we add the two equations eachother , then we can find the first number.

X + Y = 69
X - Y = 9

2X = 78

Let's divide 78 to 2 for the first number "X" .

X/2 = 39

First number is 39

X + Y = 69
So ;
39 + Y = 69
Y = 69 - 39
Y = 30

Second number is 30

Question & Answer
The Sum Of Two Numbers Is 69 And Their Difference Is 9 : 39 And 30