detailed information: The input equation set is:
 | | | | | | | | 3 | F | + | | 9 | G | + | | 27 | H | + | | 81 | I | = | | -20 | | (5) |
| | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
| | | | Question solving process:
Subtract both sides of equation (1) from both sides of equation (3) ,the equations are reduced to:
 | | | | | | | | 3 | F | + | | 9 | G | + | | 27 | H | + | | 81 | I | = | | -20 | | (5) |
| | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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Divide the two sides of equation (1) by 3, the equation can be obtained: , then subtract both sides of equation (10) from both sides of equation (4), the equations are reduced to:
 | | | | | | | | 3 | F | + | | 9 | G | + | | 27 | H | + | | 81 | I | = | | -20 | | (5) |
| | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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交After the exchange of equation (2) and equation (3), the equation system becomes:
 | | | | | | | | 3 | F | + | | 9 | G | + | | 27 | H | + | | 81 | I | = | | -20 | | (5) |
| | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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Subtract both sides of equation (2) from both sides of equation (4) ,the equations are reduced to:
 | | | | | | | | 3 | F | + | | 9 | G | + | | 27 | H | + | | 81 | I | = | | -20 | | (5) |
| | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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Divide the two sides of equation (3) by 2, the equation can be obtained: , then subtract both sides of equation (11) from both sides of equation (4), the equations are reduced to:
 | | | | | | | | 3 | F | + | | 9 | G | + | | 27 | H | + | | 81 | I | = | | -20 | | (5) |
| | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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Divide the two sides of equation (3) by 2, the equation can be obtained: , then subtract both sides of equation (12) from both sides of equation (8), the equations are reduced to:
 | | | | | | | | 3 | F | + | | 9 | G | + | | 27 | H | + | | 81 | I | = | | -20 | | (5) |
| | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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Multiply both sides of equation (4) by 2 Divide the two sides of equation (4) by 3, the equation can be obtained: , then add the two sides of equation (13) to both sides of equation (8), the equations are reduced to:
 | | | | | | | | 3 | F | + | | 9 | G | + | | 27 | H | + | | 81 | I | = | | -20 | | (5) |
| | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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Divide the two sides of equation (4) by 3, the equation can be obtained: , then add the two sides of equation (14) to both sides of equation (9), the equations are reduced to:
 | | | | | | | | 3 | F | + | | 9 | G | + | | 27 | H | + | | 81 | I | = | | -20 | | (5) |
| | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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交After the exchange of equation (5) and equation (8), the equation system becomes:
 | | | | | | | | | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
| | | 3 | F | + | | 9 | G | + | | 27 | H | + | | 81 | I | = | | -20 | | (8) |
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Multiply both sides of equation (5) by 7 Divide the two sides of equation (5) by 8, the equation can be obtained: | | | 14 3 | E | | - | 7 8 | F | = | | - | 1435 144 | (15) | , then subtract both sides of equation (15) from both sides of equation (9), the equations are reduced to:
 | | | | | | | | | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
| | | 3 | F | + | | 9 | G | + | | 27 | H | + | | 81 | I | = | | -20 | | (8) |
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Multiply both sides of equation (6) by 3, the equation can be obtained: | | 3 | F | + | | 18 | G | + | | 81 | H | + | | 324 | I | = | | 0 | (16) | , then subtract both sides of equation (16) from both sides of equation (8), the equations are reduced to:
 | | | | | | | | | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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Multiply both sides of equation (6) by 7 Divide the two sides of equation (6) by 8, the equation can be obtained: | | | 7 8 | F | + | | | 21 4 | G | + | | | 189 8 | H | + | | | 189 2 | I | = | | 0 | (17) | , then subtract both sides of equation (17) from both sides of equation (9), the equations are reduced to:
 | | | | | | | | | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
| | | - | 25 4 | G | | - | 189 8 | H | | - | 189 2 | I | = | | | 625 48 | | (9) |
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Multiply both sides of equation (7) by 9, the equation can be obtained: , then add the two sides of equation (18) to both sides of equation (8), the equations are reduced to:
 | | | | | | | | | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
| | | - | 25 4 | G | | - | 189 8 | H | | - | 189 2 | I | = | | | 625 48 | | (9) |
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Multiply both sides of equation (7) by 25 Divide the two sides of equation (7) by 4, the equation can be obtained: | | | 25 4 | G | + | | | 225 4 | H | + | | | 675 2 | I | = | | 0 | (19) | , then add the two sides of equation (19) to both sides of equation (9), the equations are reduced to:
 | | | | | | | | | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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Multiply both sides of equation (8) by 29 Divide the two sides of equation (8) by 24, the equation can be obtained: | | | 261 8 | H | + | | | 2349 8 | I | = | | - | 145 6 | (20) | , then subtract both sides of equation (20) from both sides of equation (9), the equations are reduced to:
 | | | | | | | | | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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Multiply both sides of equation (9) by 24 Divide both sides of equation (9) by 5, get the equation:, then add the two sides of equation (21) to both sides of equation (8), get the equation:
 | | | | | | | | | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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Multiply both sides of equation (9) by 16 Divide both sides of equation (9) by 15, get the equation:, then add the two sides of equation (22) to both sides of equation (7), get the equation:
 | | | | | | | | | F | + | | 6 | G | + | | 27 | H | + | | 108 | I | = | | 0 | | (6) |
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Multiply both sides of equation (9) by 32 Divide both sides of equation (9) by 15, get the equation:, then add the two sides of equation (23) to both sides of equation (6), get the equation:
Divide both sides of equation (8) by 3, get the equation:, then subtract both sides of equation (24) from both sides of equation (7), get the equation:
Subtract both sides of equation (8) from both sides of equation (6), get the equation:
Multiply both sides of equation (7) by 6, get the equation:, then subtract both sides of equation (25) from both sides of equation (6), get the equation:
Add both sides of equation (6) to both sides of equation (5), get the equation:
Multiply both sides of equation (5) by 3 Divide both sides of equation (5) by 4, get the equation:, then add the two sides of equation (26) to both sides of equation (4), get the equation:
Multiply both sides of equation (5) by 3 Divide both sides of equation (5) by 2, get the equation:, then subtract both sides of equation (27) from both sides of equation (3), get the equation:
Multiply both sides of equation (4) by 4 Divide both sides of equation (4) by 3, get the equation:, then add the two sides of equation (28) to both sides of equation (3), get the equation:
Divide both sides of equation (3) by 2, get the equation:, then add the two sides of equation (29) to both sides of equation (2), get the equation:
Multiply both sides of equation (2) by 3, get the equation:, then subtract both sides of equation (30) 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》 |