4(3x+y)-1=y-2x 12x+4y-1-y+2x=0 14x+3y-1=0 /*2 28x+6y-2=0
2(4x-y)+19=-x 8x-2y+19+x=0 9x-2y+19=0 /*3 27x-6y+57=0
55x+55=0
55x=-55
x=-1
14*(-1)+3y=1
-14+3y=1
3y=15
y=5
ответ (-1;5)
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2(x+3y)+9=x+6 2x+6y+9-x-6=0 x+6y+3=0 x+6y+3+2x-6y-30=0
3(x-2y)=x+30 3x-6y-x-30=0 2x-6y-30=0
3x-27=0
3x=27
x=9
2*9-6y=30
18-6y=30
-6y=30-18
-6y=12
y=-2
ответ(9;-2)
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5(3x+2)=7+12y 15x+10-7-12y=0 15x-12y+3=0 15x-12y+3=0
4(x+y)+x=31 4x+4y+x-31=0 5x+4y-31=0 /*3 15x+12y-93=0
-24y+96=0
-24y=-96
y=4
15x-12*4+3=0
15x-48+3=0
15x-45=0
15x=45
x=3
ответ(3;4)
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2(x+2y)-7y=6 2x+4y-7y-6=0 2x-3y-6=0 2x-3y-6+9x+3y-60=0
5(2x+y)-x=2y+60 10x+5y-x-2y-60=0 9x+3y-60=0
11x-66=0
11x=66
x=6
2*6-3y-6=0
12-3y-6=0
6-3y=0
3y=6
y=2
ответ(6;2)