4x+y=2 -2x-3y=1

system of linear equations by substitution.

x=5
y=2

nope, putting in 5,2 in to the first equation is not - 2

Substitution
first equation: y=2-4x
into second:
-2x-3(2-4x)=1
-2x+12x-6=1
10x=7
x= 7/10
then y=2-4*7/10=2-2.8= -0.8

check that.