The Sum Of Two Numbers Is 21 And Their Difference Is 7
The problem given says that 2 unknown numbers are given, whose sum is equal to 21 and the difference is 7. Let's find the two numbers :When we add the two numbers :
X + Y = 21
The difference of two numbers :
X - Y = 7
Solution :
If we add the two equations eachother , then we can find the first number.
X + Y = 21 X - Y = 7 2X = 28 |
Let's divide 28 to 2 for the first number "X" .
X/2 = 14
First number is 14
X + Y = 21
So ;
14 + Y = 21
Y = 21 - 14
Y = 7
Second number is 7
Question & Answer
The Sum Of Two Numbers Is 21 And Their Difference Is 7 : 14 And 7