.-9(x-2)-y(x-5)x=5,y=12,求式值.2.5(9+a)×b-5(5+b)×aa=5/7,求式值.3.62g+62(g+b)-bg=5/7,b=16,求式值.4.3(x+y)-5(4+x)+2yx=9,y=2,求式值.5.(x+y)(x-y)x=0.45,y=0.65,求式值.6.2ab+a×a-ba=8.2,b=0.2,求式值.7.5.6x+4(x+y)-yx=0.25.y=8,求式值.8.6.4(x+2.9)-y+2(x-y)x=12,y=0.2,求式值.9.(2.5+x)(5.2+y)x=2.3,y=5.1,求式值.10.(2x-3xy+4y)+(x+2xy-3y)x=2.y=3.5,求式值.