20(x+y)=12(y+z)=15(z+x),且xyz不等于零,求x:y:z=

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20(x+y)=12(y+z)=15(z+x),且xyz不等于零,求x:y:z=

20(x+y)=12(y+z)=15(z+x),且xyz不等于零,求x:y:z=
20(x+y)=12(y+z)=15(z+x),且xyz不等于零,求x:y:z=

20(x+y)=12(y+z)=15(z+x),且xyz不等于零,求x:y:z=
根据题意得 20(x+y)=12(y+z)
12(y+z)=15(z+x)
化简得 5x+2y=3z  ①
5x-4y=-z  ②
 ① - ② 得 6y=4z 即 y=2/3z
①*2 +② 得 15x=5z 即 x=1/3z
x:y:z=1/3z :2/3z :z =1:2:3

化简得1、2部分5x+5y=3y+3z可得5x+2y-3z=0 (1)
2、3部分4y+4z=5z+5x得5x+z-4y=0 (2)
1、3部分4x+4y=3z+3x得x+4y-3z=0 (3)
(1)-(2)得6y-4z=0
(2)+(3)得6x-2z=0
可得3y=2z 6x=2z
所以6x=3y=2z
x:y:z=1:2:3

20(x+y)=12(y+z)=15(z+x),且xyz不等于零,求x:y:z=?
1. 20,12,15的最小公倍数:60
2. 令:x + y = 3
y + z = 5
z + x = 4
3. 解出:
x = 1
y = 2
z = 3
4.得出:
x:y:z = 1:2:3