detailed information: The input equation set is:
 | | | | | -12 | A | + | | 17 | B | | -5 | C | | -60 | D | = | | 0 | | (2) |
| | | Question solving process:
Multiply both sides of equation (1) by 3 Divide the two sides of equation (1) by 13, the equation can be obtained: | | | 12 | A | | - | 36 13 | B | | - | 90 13 | C | = | | 0 | (5) | , then add the two sides of equation (5) to both sides of equation (2), the equations are reduced to:
 | | | | | | | 185 13 | B | | - | 155 13 | C | | -60 | D | = | | 0 | | (2) |
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Multiply both sides of equation (1) by 15 Divide the two sides of equation (1) by 26, the equation can be obtained: | | | 30 | A | | - | 90 13 | B | | - | 225 13 | C | = | | 0 | (6) | , then add the two sides of equation (6) to both sides of equation (3), the equations are reduced to:
 | | | | | | | 185 13 | B | | - | 155 13 | C | | -60 | D | = | | 0 | | (2) |
| | - | 155 13 | B | + | | | 620 13 | C | = | | 0 | | (3) |
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Multiply both sides of equation (2) by 31 Divide the two sides of equation (2) by 37, the equation can be obtained: | | | | 155 13 | B | | - | 4805 481 | C | | - | 1860 37 | D | = | | 0 | (7) | , then add the two sides of equation (7) to both sides of equation (3), the equations are reduced to:
 | | | | | | | 185 13 | B | | - | 155 13 | C | | -60 | D | = | | 0 | | (2) |
| | | | 1395 37 | C | | - | 1860 37 | D | = | | 0 | | (3) |
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Multiply both sides of equation (2) by 13 Divide the two sides of equation (2) by 185, the equation can be obtained: | | | B | | - | 31 37 | C | | - | 156 37 | D | = | | 0 | (8) | , then subtract both sides of equation (8) from both sides of equation (4), the equations are reduced to:
 | | | | | | | 185 13 | B | | - | 155 13 | C | | -60 | D | = | | 0 | | (2) |
| | | | 1395 37 | C | | - | 1860 37 | D | = | | 0 | | (3) |
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Divide the two sides of equation (3) by 45, the equation can be obtained: , then subtract both sides of equation (9) from both sides of equation (4), the equations are reduced to:
 | | | | | | | 185 13 | B | | - | 155 13 | C | | -60 | D | = | | 0 | | (2) |
| | | | 1395 37 | C | | - | 1860 37 | D | = | | 0 | | (3) |
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Multiply both sides of equation (4) by 1395 Divide both sides of equation (4) by 148, get the equation:, then add the two sides of equation (10) to both sides of equation (3), get the equation:
 | | | | | | | 185 13 | B | | - | 155 13 | C | | -60 | D | = | | 0 | | (2) |
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Multiply both sides of equation (4) by 1665 Divide both sides of equation (4) by 148, get the equation:, then add the two sides of equation (11) to both sides of equation (2), get the equation:
 | | | | | | | 185 13 | B | | - | 155 13 | C | = | | 540 | | (2) |
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Multiply both sides of equation (3) by 37 Divide both sides of equation (3) by 117, get the equation:, then add the two sides of equation (12) to both sides of equation (2), get the equation:
Multiply both sides of equation (3) by 74 Divide both sides of equation (3) by 93, get the equation:, then add the two sides of equation (13) to both sides of equation (1), get the equation:
Multiply both sides of equation (2) by 156 Divide both sides of equation (2) by 185, get the equation:, then add the two sides of equation (14) to both sides of equation (1), get the equation:
The coefficient of the unknown number is reduced to 1, and the equations are reduced to:
Therefore, the solution of the equation set is:
解方程组的详细方法请参阅:《多元一次方程组的解法》 |