detailed information: The input equation set is:
| | | | 420 | x | + | | 220 | y | + | | 200 | z | = | | 4 | | (1) |
| | 220 | x | + | | 520 | y | | -200 | z | = | | 0 | | (2) |
| | 200 | x | | -200 | y | + | | 500 | z | = | | 0 | | (3) |
| Question solving process:
Multiply both sides of equation (1) by 11 Divide the two sides of equation (1) by 21, the equation can be obtained: | | 220 | x | + | | | 2420 21 | y | + | | | 2200 21 | z | = | | | 44 21 | (4) | , then subtract both sides of equation (4) from both sides of equation (2), the equations are reduced to:
| | | | 420 | x | + | | 220 | y | + | | 200 | z | = | | 4 | | (1) |
| | | 8500 21 | y | | - | 6400 21 | z | = | | - | 44 21 | | (2) |
| | 200 | x | | -200 | y | + | | 500 | z | = | | 0 | | (3) |
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Multiply both sides of equation (1) by 10 Divide the two sides of equation (1) by 21, the equation can be obtained: | | 200 | x | + | | | 2200 21 | y | + | | | 2000 21 | z | = | | | 40 21 | (5) | , then subtract both sides of equation (5) from both sides of equation (3), the equations are reduced to:
| | | | 420 | x | + | | 220 | y | + | | 200 | z | = | | 4 | | (1) |
| | | 8500 21 | y | | - | 6400 21 | z | = | | - | 44 21 | | (2) |
| - | 6400 21 | y | + | | | 8500 21 | z | = | | - | 40 21 | | (3) |
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Multiply both sides of equation (2) by 64 Divide the two sides of equation (2) by 85, the equation can be obtained: | | | 6400 21 | y | | - | 81920 357 | z | = | | - | 2816 1785 | (6) | , then add the two sides of equation (6) to both sides of equation (3), the equations are reduced to:
| | | | 420 | x | + | | 220 | y | + | | 200 | z | = | | 4 | | (1) |
| | | 8500 21 | y | | - | 6400 21 | z | = | | - | 44 21 | | (2) |
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Multiply both sides of equation (3) by 5440 Divide both sides of equation (3) by 3129, get the equation: | | | 953600 3129 | z | = | | - | 18944 3129 | (7) | , then add the two sides of equation (7) to both sides of equation (2), get the equation:
| | | | 420 | x | + | | 220 | y | + | | 200 | z | = | | 4 | | (1) |
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Multiply both sides of equation (3) by 170 Divide both sides of equation (3) by 149, get the equation:, then subtract both sides of equation (8) from both sides of equation (1), get the equation:
| | | | 420 | x | + | | 220 | y | = | | | 1188 149 | | (1) |
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Multiply both sides of equation (2) by 231 Divide both sides of equation (2) by 425, get the equation:, then subtract both sides of equation (9) from 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》 |