The Sum Of Two Numbers Is 21 And Their Difference Is 9
The problem given says that 2 unknown numbers are given, whose sum is equal to 21 and the difference is 9. Let's find the two numbers :When we add the two numbers :
X + Y = 21
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 = 21 X - Y = 9 2X = 30 |
Let's divide 30 to 2 for the first number "X" .
X/2 = 15
First number is 15
X + Y = 21
So ;
15 + Y = 21
Y = 21 - 15
Y = 6
Second number is 6
Question & Answer
The Sum Of Two Numbers Is 21 And Their Difference Is 9 : 15 And 6