Question

Solve

5x + y = 2
4x + y = 4

Answer 1

from first equation
5x+y=2
y=2-5x

in second equation
4x+y=4
4x+(2-5x)=4
4x+2-5x=4
-x+2=4
-x=4-2
-x=2
x=-2


y=2-5x =2-(5*-2)=2-(-10)=2+10 =12

Answer 2

or you solve two equations together
as u subtract second equation from first

(5x-4x) + (y-y) =2-4
x+0=-2
x=-2

in first equation
5x+y=2
5*(-2)+y=2
-10+y=2
y=10+2
y=12