七年级数学下册方程组练习题.doc

二元一次/三元一次方程组练习
2x+9y=81 9x+4y=35
3x+y=34 8x+3y=30

7x+2y=52 x+2y=21
7x+4y=62 3x+5y=56

4x+6y=54 2x+y=7
9x+2y=87 2x+5y=19

5x+7y=52 5x+5y=65
5x+2y=22 7x+7y=203

8x+4y=56 x+8y=15
x+4y=21 4x+y=29

5x+7y=41 7x+5y=54
5x+8y=44 3x+4y=38

3x+6y=24 9x+2y=62
9x+5y=46 4x+3y=36

9x+4y=46 9x+3y=99
7x+4y=42 4x+7y=95

9x+7y=13 3x+8y=51
4x+y=41 x+6y=27

9x+2y=38 5x+5y=45
3x+6y=18 7x+9y=69

8x+2y=28 5x+4y=52
7x+8y=62 7x+6y=74

x+6y=14 7x+4y=67
3x+3y=27 2x+8y=26

7x+y=9 6x+6y=48
4x+6y=16 6x+3y=42

8x+2y=16 6x+8y=68
7x+y=11 7x+6y=66

4x+9y=77 2x+2y=22
8x+6y=94 7x+2y=47

2x+7y-z=24 x+y+z=7
4x-4y+z=-3 2x+y-z=5
x+y=5 x-y-2z=4

a+b+c=0 5x-4y+4z=13
4a+2b+c=3 2x+7y-3z=19
9a-3b+c=28 3x+2y-z=18

a+b+c=-2 3x-y+z=3
a-b+c=20 2x+y-3z=11
a+b=0 x+y+z=12

a+b+c=-4 x-2y-3z+18=0
49a+7b+c=8 x+3y-2z-8=0
25a+5b+c=0 x+y+2z-24=0

x+y=3 x+y+z=12
2x-y+2z=2 x+2y-z=6
x-y-z=-3 3x-y+z=10

2x+3y=6 2a+b+c=0
x-y+2z=-1 4a+2b+c=5
x+2y-z=5 2a-b+c=4

3x-y+z=4 x+y-z=5
x+y+z=6 2x+3y+z=10
2x+3y-z=12 x-2y-z=10

x+y+z=6 x-y-5z=4
x-y=1 2x+y-3z=10
2x-y+z=5 3x+y+z=8

3x-y+2z=3 3x+2y+5z=2
2x+y-3z=11 x-2y-z=6
x+y+z=12 4x+2y-7z=30

x+2y+3z=14 x-y+z=1
2x+y+z=7 3x+y-2z=2
3x+y+2z=11 x+2y-z=3

x+2y+3z=5 x+y+z=6
2x+3y+6z=9 2x+3y+z=11
5x+3y+9z=15 3x-y-z=-2

3x-y+z=4 x+2y+z=2
2x+3y-z+12 x-4y+z=5
x+y+z=6 2x-2y-5z=0

- 11 -