detailed information: The input equation set is:
| | | | | 13 20 | A | | - | 1 5 | B | | - | 1 5 | C | | - | 1 5 | D | = | | -2 | | (1) |
| - | 1 5 | A | + | | | 6 5 | B | | - | 1 5 | D | = | | 4 | | (2) |
| - | 1 5 | A | + | | | 1 5 | C | | - | 1 5 | D | = | | -2 | | (3) |
| - | 1 5 | A | | - | 1 5 | B | | - | 1 5 | C | + | | | 6 5 | D | = | | 4 | | (4) |
| Question solving process:
Multiply both sides of equation (1) by 4 Divide the two sides of equation (1) by 13, the equation can be obtained: | | | 1 5 | A | | - | 4 65 | B | | - | 4 65 | C | | - | 4 65 | D | = | | - | 8 13 | (5) | , then add the two sides of equation (5) to both sides of equation (2), the equations are reduced to:
| | | | | 13 20 | A | | - | 1 5 | B | | - | 1 5 | C | | - | 1 5 | D | = | | -2 | | (1) |
| | | 74 65 | B | | - | 4 65 | C | | - | 17 65 | D | = | | | 44 13 | | (2) |
| - | 1 5 | A | + | | | 1 5 | C | | - | 1 5 | D | = | | -2 | | (3) |
| - | 1 5 | A | | - | 1 5 | B | | - | 1 5 | C | + | | | 6 5 | D | = | | 4 | | (4) |
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Multiply both sides of equation (1) by 4 Divide the two sides of equation (1) by 13, the equation can be obtained: | | | 1 5 | A | | - | 4 65 | B | | - | 4 65 | C | | - | 4 65 | D | = | | - | 8 13 | (6) | , then add the two sides of equation (6) to both sides of equation (3), the equations are reduced to:
| | | | | 13 20 | A | | - | 1 5 | B | | - | 1 5 | C | | - | 1 5 | D | = | | -2 | | (1) |
| | | 74 65 | B | | - | 4 65 | C | | - | 17 65 | D | = | | | 44 13 | | (2) |
| - | 4 65 | B | + | | | 9 65 | C | | - | 17 65 | D | = | | - | 34 13 | | (3) |
| - | 1 5 | A | | - | 1 5 | B | | - | 1 5 | C | + | | | 6 5 | D | = | | 4 | | (4) |
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Multiply both sides of equation (1) by 4 Divide the two sides of equation (1) by 13, the equation can be obtained: | | | 1 5 | A | | - | 4 65 | B | | - | 4 65 | C | | - | 4 65 | D | = | | - | 8 13 | (7) | , then add the two sides of equation (7) to both sides of equation (4), the equations are reduced to:
| | | | | 13 20 | A | | - | 1 5 | B | | - | 1 5 | C | | - | 1 5 | D | = | | -2 | | (1) |
| | | 74 65 | B | | - | 4 65 | C | | - | 17 65 | D | = | | | 44 13 | | (2) |
| - | 4 65 | B | + | | | 9 65 | C | | - | 17 65 | D | = | | - | 34 13 | | (3) |
| - | 17 65 | B | | - | 17 65 | C | + | | | 74 65 | D | = | | | 44 13 | | (4) |
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Multiply both sides of equation (2) by 2 Divide the two sides of equation (2) by 37, the equation can be obtained: | | | 4 65 | B | | - | 8 2405 | C | | - | 34 2405 | D | = | | | 88 481 | (8) | , then add the two sides of equation (8) to both sides of equation (3), the equations are reduced to:
| | | | | 13 20 | A | | - | 1 5 | B | | - | 1 5 | C | | - | 1 5 | D | = | | -2 | | (1) |
| | | 74 65 | B | | - | 4 65 | C | | - | 17 65 | D | = | | | 44 13 | | (2) |
| | | 5 37 | C | | - | 51 185 | D | = | | - | 90 37 | | (3) |
| - | 17 65 | B | | - | 17 65 | C | + | | | 74 65 | D | = | | | 44 13 | | (4) |
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Multiply both sides of equation (2) by 17 Divide the two sides of equation (2) by 74, the equation can be obtained: | | | 17 65 | B | | - | 34 2405 | C | | - | 289 4810 | D | = | | | 374 481 | (9) | , then add the two sides of equation (9) to both sides of equation (4), the equations are reduced to:
| | | | | 13 20 | A | | - | 1 5 | B | | - | 1 5 | C | | - | 1 5 | D | = | | -2 | | (1) |
| | | 74 65 | B | | - | 4 65 | C | | - | 17 65 | D | = | | | 44 13 | | (2) |
| | | 5 37 | C | | - | 51 185 | D | = | | - | 90 37 | | (3) |
| - | 51 185 | C | + | | | 399 370 | D | = | | | 154 37 | | (4) |
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Multiply both sides of equation (3) by 51 Divide the two sides of equation (3) by 25, the equation can be obtained: | | | 51 185 | C | | - | 2601 4625 | D | = | | - | 918 185 | (10) | , then add the two sides of equation (10) to both sides of equation (4), the equations are reduced to:
| | | | | 13 20 | A | | - | 1 5 | B | | - | 1 5 | C | | - | 1 5 | D | = | | -2 | | (1) |
| | | 74 65 | B | | - | 4 65 | C | | - | 17 65 | D | = | | | 44 13 | | (2) |
| | | 5 37 | C | | - | 51 185 | D | = | | - | 90 37 | | (3) |
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Multiply both sides of equation (4) by 850 Divide both sides of equation (4) by 1591, get the equation:, then add the two sides of equation (11) to both sides of equation (3), get the equation:
| | | | | 13 20 | A | | - | 1 5 | B | | - | 1 5 | C | | - | 1 5 | D | = | | -2 | | (1) |
| | | 74 65 | B | | - | 4 65 | C | | - | 17 65 | D | = | | | 44 13 | | (2) |
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Multiply both sides of equation (4) by 850 Divide both sides of equation (4) by 1677, get the equation:, then add the two sides of equation (12) to both sides of equation (2), get the equation:
| | | | | 13 20 | A | | - | 1 5 | B | | - | 1 5 | C | | - | 1 5 | D | = | | -2 | | (1) |
| | | 74 65 | B | | - | 4 65 | C | = | | | 4996 1677 | | (2) |
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Multiply both sides of equation (4) by 50 Divide both sides of equation (4) by 129, get the equation:, then add the two sides of equation (13) to both sides of equation (1), get the equation:
| | | | | 13 20 | A | | - | 1 5 | B | | - | 1 5 | C | = | | - | 298 129 | | (1) |
| | | 74 65 | B | | - | 4 65 | C | = | | | 4996 1677 | | (2) |
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Multiply both sides of equation (3) by 148 Divide both sides of equation (3) by 325, get the equation:, then add the two sides of equation (14) to both sides of equation (2), get the equation:
| | | | | 13 20 | A | | - | 1 5 | B | | - | 1 5 | C | = | | - | 298 129 | | (1) |
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Multiply both sides of equation (3) by 37 Divide both sides of equation (3) by 25, get the equation:, then add the two sides of equation (15) to both sides of equation (1), get the equation:
| | | | | 13 20 | A | | - | 1 5 | B | = | | - | 844 129 | | (1) |
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Multiply both sides of equation (2) by 13 Divide both sides of equation (2) by 74, get the equation:, then add the two sides of equation (16) 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:
Convert the solution of the equation set to decimals:
解方程组的详细方法请参阅:《多元一次方程组的解法》 |