1995X=1996Y,73X-74Y=1922;巧消常数项法7x+23y=10;17X+16Y=20;
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1995X=1996Y,73X-74Y=1922;巧消常数项法7x+23y=10;17X+16Y=20;
1995x=1996y
1995x-1995y=y
1995(x-y)=y.①
73x-74y=1922
73x-73y=1922+y
73(x-y)=1922+y.②
①-②,得1922(x-y)=-1922
x-y=-1
x=y-1
∴1995(y-1)=1996y
y=-1995.
∴x=-1996.
(联立不起来- -电脑上打不出)
7x+23y=10.③
17x+16y=20.④
④-2×③,得
3x-30y=0
x=10y.
∴x=100/93,y=10/93.
1995x-1995y=y
1995(x-y)=y.①
73x-74y=1922
73x-73y=1922+y
73(x-y)=1922+y.②
①-②,得1922(x-y)=-1922
x-y=-1
x=y-1
∴1995(y-1)=1996y
y=-1995.
∴x=-1996.
(联立不起来- -电脑上打不出)
7x+23y=10.③
17x+16y=20.④
④-2×③,得
3x-30y=0
x=10y.
∴x=100/93,y=10/93.
x+y=5; x^y+y^x=17
X+Y=7(100X+Y)-(10Y+X)=(10Y+X)-(10X+Y)
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