X=(Y+Z+200)*1/4Y=(X+Z+200)*2/7Z=(X+Y+200)*8/7thank you

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X=(Y+Z+200)*1/4Y=(X+Z+200)*2/7Z=(X+Y+200)*8/7thank you
X=(Y+Z+200)*1/4
Y=(X+Z+200)*2/7
Z=(X+Y+200)*8/7
thank you

X=(Y+Z+200)*1/4Y=(X+Z+200)*2/7Z=(X+Y+200)*8/7thank you
把分母移过来化为x.y.z的加减方程,再相加相减消去一个相同的字母,在解个二元一次方程组就行拉(手机用户不方便详细过程)

化简得4X-Y-Z=200 (1)
2X-7Y+2Z=400 (2)
8X+8Y-9Z=-1600 (3)
(1)*2=10X-9Y=800
(1)*9=28X-17Y=3400
∴X=8500/41 Y=5800/41 Z=20000/41

X=(Y+Z+200)*1/4 1
Y=(X+Z+200)*2/7 2
Z=(X+Y+200)*8/7 3
1:两边乘4,4X=Y+Z+200,4X-Y-Z=200 ①
2:两边乘7 7Y=2X+2Z+400,-2X+7Y-2Z=400 ②
3:两边乘7 7Z=8X+8Y+1600,-8X-8Y+7Z=1600 ③
①乘7:28X-7Y-7Z=140...

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X=(Y+Z+200)*1/4 1
Y=(X+Z+200)*2/7 2
Z=(X+Y+200)*8/7 3
1:两边乘4,4X=Y+Z+200,4X-Y-Z=200 ①
2:两边乘7 7Y=2X+2Z+400,-2X+7Y-2Z=400 ②
3:两边乘7 7Z=8X+8Y+1600,-8X-8Y+7Z=1600 ③
①乘7:28X-7Y-7Z=1400 ④
④+②:26X-9Z=1800 ⑥
①乘8:32X-8Y-8Z=1600 ⑤
⑤减③:40X-15Z=0 得到X=3/8Z代入⑥,Z=2400.X=900
代入①最后得到Y=600

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解:X=(Y+Z+200)*1/4 ....a
Y=(X+Z+200)*2/7 .....b
Z=(X+Y+200)*8/7 .....c
a:两边乘4,4X=Y+Z+200,4X-Y-Z=200 ①
b:两边乘7 7Y=2X+2Z+400,7Y-2X-2Z=400 ②
c:两边乘7 7Z=8X+8Y+1600,7Z-8X-8Y=1600 ③
①乘7...

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解:X=(Y+Z+200)*1/4 ....a
Y=(X+Z+200)*2/7 .....b
Z=(X+Y+200)*8/7 .....c
a:两边乘4,4X=Y+Z+200,4X-Y-Z=200 ①
b:两边乘7 7Y=2X+2Z+400,7Y-2X-2Z=400 ②
c:两边乘7 7Z=8X+8Y+1600,7Z-8X-8Y=1600 ③
①乘7:28X-7Y-7Z=1400 ④
④+②:26X-9Z=1800 ⑥
①乘8:32X-8Y-8Z=1600 ⑤
⑤减③:40X-15Z=0 得到X=3/8Z代入⑥,Z=2400.X=900
代入①最后得到Y=600

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