2. •
-
•
•
-

3. •
•
•

4. I. x-y=8
II. 3x+2y=24
I. x=8+y
II. 3x+2y=24
-x
3(8+y)+2y=24
y+2y=24
5y=0
y=0
-y
x-0=8
x=8
y=0
x=8

5. I. x-y=8
II. 3x+2y=24
I. x-y=8
II. 3x+2y=24
I. - x+3y=-24
II. 3x+2y=24
y=0
y=0
-y
x-0=8
x=8
y=0
x=8

6. I. x-y=8
II. 3x+2y=24
yx
-80
08
yx
120
08
x-y=83x+2y=2
4

7. I. 2(3x+5)-7(y+3)=-2(1+y)-42
II. 2(1-2x)+5(2y-1)=-5y+54
I. x+10-7y-21=-2-2y-42
II. 2-4x+10y-5=-5y+54
I. 6x-5y=-33
II. -4x+15y=57
I. y=33/5+6/5*x
II. -4x+15y=57
-y
-x+15(33/5+6/5*x)=57
-x+99+18x=57
+14x=-42
x=-3
-x
-- y=-33
-18-5y=-33
-5y=-15
y=3
y=3
x=-3

8. I. 2(3x+5)-7(y+3)=-2(1+y)-42
II. 2(1-2x)+5(2y-1)=-5y+54
I. x+10-7y-21=-2-2y-42
II. 2-4x+10y-5=-5y+54
I. 6x-5y=-33
II. -4x+15y=57
-
I. x-15y=-99
II. -4x+15y=57
x=-42
x=-3
-x
-- y=-33
-18-5y=-33
-5y=-15
y=3
y=3
x=-3

9. I. 2(3x+5)-7(y+3)=-2(1+y)-42
II. 2(1-2x)+5(2y-1)=-5y+54
yx
33/50
0-33/6
yx
57/150
0-57/4
2(3x+5)-7(y+3)=-2(1+y)-422(1-2x)+5(2y-1)=-5y+54

10. I. (-x+4y)/7+(-2y-1)/14=1+x/2
II. (x+1)/4+(-2y+3x)/3+x=(y-3)/6
I. - x+8y)-(2y-1)=14+7x
II. 3(x+1)-4(2y-3x)+12x=2(y-3)
1. -2x+8y-2y-1=14+7x
2. 3x+3-8y+12x+12x=2y-6
I. -9x+6y=15
II. 27x-10y=-9
y=15/6+9/15*x
27x-10y=-9
-y
x-10*(15/6+9/15*x)=-9
x-150/6-90/15*x=-9
x=1
-x
-y=15
6y=24
y=4
y=4
x=1

11. I. (-x+4y)/7+(-2y-1)/14=1+x/2
II. (x+1)/4+(-2y+3x)/3+x=(y-3)/6
I. - x+8y)-(2y-1)=14+7x
II. 3(x+1)-4(2y-3x)+12x=2(y-3)
I. -2x+8y-2y-1=14+7x
II. 3x+3-8y+12x+12x=2y-6
I. -9x+6y=15
II. 27x-10y=-9
-
-x+18y=45
27x-10y=-9
y=36
y=4
-y
-x+6*4=15
-9x=-9
x=1
y=4
x=1

12. I. (-x+4y)/7+(-2y-1)/14=1+x/2
II. (x+1)/4+(-2y+3x)/3+x=(y-3)/6
yx
2.50
0-15/9
yx
9/100
0-1/3
(-x+4y)/7+(-2y-1)/14=1+x/2(x+1)/4+(-2y+3x)/3+x=(y-
3)/6

13. .1
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14. .1
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