先化简,再求值:(1)(x²+2x)/(x²-x),其中x=10;(2)(3x²-xy)/9x²-6xy+y²,其中x=-8,y=2.

先化简,再求值:(1)(x²+2x)/(x²-x),其中x=10;(2)(3x²-xy)/9x²-6xy+y²,其中x=-8,y=2.
先化简,再求值:(1)(x²+2x)/(x²-x),其中x=10;
(2)(3x²-xy)/9x²-6xy+y²,其中x=-8,y=2.

先化简,再求值:(1)(x²+2x)/(x²-x),其中x=10;(2)(3x²-xy)/9x²-6xy+y²,其中x=-8,y=2.
(x²+2x)/(x²-x)
=x(x+2)/[x(x-1)]
=(x+2)/(x-1)
=(10+2)/(10-1)
=12/9
=4/3
(3x²-xy)/(9x²-6xy+y²)
=x(3x-y)/(3x-y)²
=x/(3x-y)
=-8/[3*(-8)-2]
=-8/[-24-2]
=-8/(-26)
=4/13