Question

Find two numbers such that twice of the first added to the second gives 21, and twice the second added to first gives 27

Answer 1

Let the first no. be x and second be y
2x+y=21
x+2y=27
multiply the second eq. by 2 then subtract both the equation
2x+y=21
-
2x+4y=54
------------
-3y=-33
y=11

2x+y=21
2x=21-11
2x=10
x=5
Ans...therefore the numbers are 5 and 11

Answer 2

2x+y:21, y:21-2x
x+2y:27,
x+42-4x:27
3x:15
x:5, y:11