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On line solution of multivariate equations：
    First set the elements of the equation (i.e. the number of unknowns), then click the "Next" button to enter the coefficients of each element of the equation set, and click the "Next" button to obtain the solution of the equation set.
    Note that the coefficients of each element of the equation system can only be numbers, not algebraic expressions (including mathematical functions).
    Current location：Equations > Multivariate equations > Answer
detailed information：
The input equation set is:
 A + B + C + D = 7168    (1)
- 
39
100
A + 
61
100
B = 0    (2)
 
61
100
C - 
61
100
D = 0    (3)
 
61
100
B - 
61
100
D = 0    (4)
Question solving process:

Multiply both sides of equation (1) by 39
Divide the two sides of equation (1) by 100, the equation can be obtained:
         
39
100
A + 
39
100
B + 
39
100
C + 
39
100
D = 
69888
25
    (5)
, then add the two sides of equation (5) to both sides of equation (2), the equations are reduced to:
 A + B + C + D = 7168    (1)
 B + 
39
100
C + 
39
100
D = 
69888
25
    (2)
 
61
100
C - 
61
100
D = 0    (3)
 
61
100
B - 
61
100
D = 0    (4)

Multiply both sides of equation (2) by 61
Divide the two sides of equation (2) by 100, the equation can be obtained:
         
61
100
B + 
2379
10000
C + 
2379
10000
D = 
1065792
625
    (6)
, then subtract both sides of equation (6) from both sides of equation (4), the equations are reduced to:
 A + B + C + D = 7168    (1)
 B + 
39
100
C + 
39
100
D = 
69888
25
    (2)
 
61
100
C - 
61
100
D = 0    (3)
- 
2379
10000
C - 
8479
10000
D = - 
1065792
625
    (4)

Multiply both sides of equation (3) by 39
Divide the two sides of equation (3) by 100, the equation can be obtained:
         
2379
10000
C - 
2379
10000
D = 0    (7)
, then add the two sides of equation (7) to both sides of equation (4), the equations are reduced to:
 A + B + C + D = 7168    (1)
 B + 
39
100
C + 
39
100
D = 
69888
25
    (2)
 
61
100
C - 
61
100
D = 0    (3)
- 
5429
5000
D = - 
1065792
625
    (4)

Multiply both sides of equation (4) by 50
Divide both sides of equation (4) by 89, get the equation：
        - 
61
100
D = - 
2131584
2225
    (8)
, then subtract both sides of equation (8) from both sides of equation (3), get the equation：
 A + B + C + D = 7168    (1)
 B + 
39
100
C + 
39
100
D = 
69888
25
    (2)
 
61
100
C = 
2131584
2225
    (3)
- 
5429
5000
D = - 
1065792
625
    (4)

Multiply both sides of equation (4) by 1950
Divide both sides of equation (4) by 5429, get the equation：
        - 
39
100
D = - 
1362816
2225
    (9)
, then add the two sides of equation (9) to both sides of equation (2), get the equation：
 A + B + C + D = 7168    (1)
 B + 
39
100
C = 
4857216
2225
    (2)
 
61
100
C = 
2131584
2225
    (3)
- 
5429
5000
D = - 
1065792
625
    (4)

Multiply both sides of equation (4) by 5000
Divide both sides of equation (4) by 5429, get the equation：
        -1D = - 
139776
89
    (10)
, then add the two sides of equation (10) to both sides of equation (1), get the equation：
 A + B + C = 
498176
89
    (1)
 B + 
39
100
C = 
4857216
2225
    (2)
 
61
100
C = 
2131584
2225
    (3)
- 
5429
5000
D = - 
1065792
625
    (4)

Multiply both sides of equation (3) by 39
Divide both sides of equation (3) by 61, get the equation：
         
39
100
C = 
1362816
2225
    (11)
, then subtract both sides of equation (11) from both sides of equation (2), get the equation：
 A + B + C = 
498176
89
    (1)
 B = 
139776
89
    (2)
 
61
100
C = 
2131584
2225
    (3)
 D = 
139776
89
    (4)

Multiply both sides of equation (3) by 100
Divide both sides of equation (3) by 61, get the equation：
         C = 
139776
89
    (12)
, then subtract both sides of equation (12) from both sides of equation (1), get the equation：
 A + B = 
358400
89
    (1)
 B = 
139776
89
    (2)
 
61
100
C = 
2131584
2225
    (3)
 D = 
139776
89
    (4)

Subtract both sides of equation (2) from both sides of equation (1), get the equation：
 A = 
218624
89
    (1)
 B = 
139776
89
    (2)
 C = 
139776
89
    (3)
 D = 
139776
89
    (4)

The coefficient of the unknown number is reduced to 1, and the equations are reduced to：
 A = 
218624
89
    (1)
 B = 
139776
89
    (2)
 C = 
139776
89
    (3)
 D = 
139776
89
    (4)


Therefore, the solution of the equation set is:
A = 
218624
89
B = 
139776
89
C = 
139776
89
D = 
139776
89


Convert the solution of the equation set to decimals:
A = 2456.449438
B = 1570.516854
C = 1570.516854
D = 1570.516854

解方程组的详细方法请参阅：《多元一次方程组的解法》
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