2գ
x-y+=0
3x+y-4-=0
3x-3y+6=0
3x+y-4=0
3x-3y+6- (3x+y-4)= 0
3x-3y+6-3x-y+4=0
-3y+6-y+4=0
-3y-y+6+4=0
-4y=-10
y= -10/-4
y=2, 5
x=y-2=2, 5-2=0,5
ա){x+ 1y=11
{2x+y=18
Հանման 2x+ 1y- (x+ 1y)= 18-11
2x-x=7
x=7
7+y=11
y=4
{ x+5y-45=0 1, 5 3x+ 15y-135=0
{3x-y-23=0 3 , -1 3x-y-23=0
3x+ 15y-135-(3x-y-23)=0
3x+15y-135-3x+y+23=0
15y+y-135+23=0
16y= 112
y=7
x+35-45=0
x=10