3x + y = 5..........(1)
x - 2y = 4 ..........(2)
First let us use the elimination method.
Let us multiply (1) by 2 and add to (2):
==> 7x = 14
==> x = 2
Now using the substitution method substitute x velue in (2)
x-2y = 4
2 - 2y = 4
2-4 = 2y
-2 = 2y
==> y= -1
The solution is:
x= 2 and y= -1