详细信息: 输入的方程组为:
 | | | | | | | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (4) |
| | | | | | A | + | | B | + | | C | + | | D | + | | E | + | | F | + | | G | + | | H | = | | | 254 5 | | (8) |
| 解题过程:
用第 (5) 式两边同时 减去 第 (1) 等式两边,方程组化为:
 | | | | | | | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (4) |
| | | | | | A | + | | B | + | | C | + | | D | + | | E | + | | F | + | | G | + | | H | = | | | 254 5 | | (8) |
|
用第 (8) 式两边同时 减去 第 (1) 等式两边,方程组化为:
 | | | | | | | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (4) |
| | | | | | C | + | | D | + | | E | + | | F | + | | G | + | | H | = | | | 224 5 | | (8) |
|
交换第(2)和第(5)式后,方程组化为:
 | | | | | | | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (4) |
| | | | | | C | + | | D | + | | E | + | | F | + | | G | + | | H | = | | | 224 5 | | (8) |
|
用第 (6) 式两边同时 加上 第 (2) 等式两边,方程组化为:
 | | | | | | | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (4) |
| | | | | | C | + | | D | + | | E | + | | F | + | | G | + | | H | = | | | 224 5 | | (8) |
|
交换第(3)和第(5)式后,方程组化为:
 | | | | | | | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (4) |
| | | | | | C | + | | D | + | | E | + | | F | + | | G | + | | H | = | | | 224 5 | | (8) |
|
用第 (6) 式两边同时 减去 第 (3) 等式两边,方程组化为:
 | | | | | | | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (4) |
| | | -1 | D | + | | E | + | | F | = | | - | 167 50 | | (6) |
| | | | C | + | | D | + | | E | + | | F | + | | G | + | | H | = | | | 224 5 | | (8) |
|
用第 (8) 式两边同时 减去 第 (3) 等式两边,方程组化为:
 | | | | | | | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (4) |
| | | -1 | D | + | | E | + | | F | = | | - | 167 50 | | (6) |
| | | | E | + | | F | + | | G | + | | H | = | | | 263 10 | | (8) |
|
交换第(4)和第(6)式后,方程组化为:
 | | | | | | | -1 | D | + | | E | + | | F | = | | - | 167 50 | | (4) |
| | | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (6) |
| | | | E | + | | F | + | | G | + | | H | = | | | 263 10 | | (8) |
|
用第 (7) 式两边同时 加上 第 (4) 等式两边,方程组化为:
 | | | | | | | -1 | D | + | | E | + | | F | = | | - | 167 50 | | (4) |
| | | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (6) |
| | | | E | + | | F | + | | G | + | | H | = | | | 263 10 | | (8) |
|
交换第(5)和第(6)式后,方程组化为:
 | | | | | | | -1 | D | + | | E | + | | F | = | | - | 167 50 | | (4) |
| | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (5) |
| | | | | E | + | | F | + | | G | + | | H | = | | | 263 10 | | (8) |
|
用第 (7) 式两边同时 减去 第 (5) 等式两边,方程组化为:
 | | | | | | | -1 | D | + | | E | + | | F | = | | - | 167 50 | | (4) |
| | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (5) |
| | | | | E | + | | F | + | | G | + | | H | = | | | 263 10 | | (8) |
|
用第 (8) 式两边同时 减去 第 (5) 等式两边,方程组化为:
 | | | | | | | -1 | D | + | | E | + | | F | = | | - | 167 50 | | (4) |
| | | E | + | | F | + | | G | + | | H | = | | | 261 10 | | (5) |
| | | |
由第(8)方程式可以看出,该方程组无解。
解方程组的详细方法请参阅:《多元一次方程组的解法》 |