Mathematics
语言：中文
Language:English

current location：Equations > Multivariate equations > Answer
Detailed information：
The input equation set is:
 2x + y = 5    (1)
 3x + y = -15    (2)
Question solving process:

Multiply both sides of equation (1) by 3
Divide the two sides of equation (1) by 2, the equation can be obtained:
         3x + 
3
2
y = 
15
2
    (3)
, then subtract both sides of equation (3) from both sides of equation (2), the equations are reduced to:
 2x + y = 5    (1)
- 
1
2
y = - 
45
2
    (2)

Multiply both sides of equation (2) by 2, get the equation：
        -1y = -45    (4)
, then add the two sides of equation (4) to both sides of equation (1), get the equation：
 2x = -40    (1)
- 
1
2
y = - 
45
2
    (2)

The coefficient of the unknown number is reduced to 1, and the equations are reduced to：
 x = -20    (1)
 y = 45    (2)


Therefore, the solution of the equation set is:
x = -20
y = 45

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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