Answer :
{-2x+y=12 => y=12+2x
{3x+2y=38
3x+2(12+2x)=38
3x+24+4x=38 /-24
7x=14 /:7
x=2
y=12+2*2=12+4=16
y=16
Solution: (2; 16)
{-2x+y=12 => y=12+2x
{3x+2y=38
3x+2(12+2x)=38
3x+24+4x=38 /-24
7x=14 /:7
x=2
y=12+2*2=12+4=16
y=16
Solution: (2; 16)