Mathematics
语言：中文
Language:English
current location：Equations > Multivariate equations > Answer
Detailed information：
The input equation set is:
 x + z = 18    (1)
-1x + y = 7    (2)
 x + y = 17    (3)
Question solving process:

Add both sides of equation (1) to both sides of equation (2) ,the equations are reduced to:
 x + z = 18    (1)
 y + z = 25    (2)
 x + y = 17    (3)

Subtract both sides of equation (1) from both sides of equation (3) ,the equations are reduced to:
 x + z = 18    (1)
 y + z = 25    (2)
 y -1z = -1    (3)

Subtract both sides of equation (2) from both sides of equation (3) ,the equations are reduced to:
 x + z = 18    (1)
 y + z = 25    (2)
-2z = -26    (3)

Divide both sides of equation (3) by 2, get the equation：
        -1z = -13    (4)
, then add the two sides of equation (4) to both sides of equation (2), get the equation：
 x + z = 18    (1)
 y = 12    (2)
-2z = -26    (3)

Divide both sides of equation (3) by 2, get the equation：
        -1z = -13    (5)
, then add the two sides of equation (5) to both sides of equation (1), get the equation：
 x = 5    (1)
 y = 12    (2)
-2z = -26    (3)

The coefficient of the unknown number is reduced to 1, and the equations are reduced to：
 x = 5    (1)
 y = 12    (2)
 z = 13    (3)


Therefore, the solution of the equation set is:
x = 5
y = 12
z = 13

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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