1、(2x²-50)÷(-x²-10x-25)
=2(x²-25)÷[-(x²+10x+25)]
=-2(x+5)(x-5)÷(x+5)²
=-(2x-10)/(x+5)
2、(xy-2x-2y+4)÷(4-2x) 【改个地方】
=(x-2)(y-2)÷[-2(x-2)]
=-(y-2)/2
=(2-y)/2
=1-y/2
1、(2x²-50)÷(-x²-10x-25)
=2(x²-25)÷[-(x²+10x+25)]
=-2(x+5)(x-5)÷(x+5)²
=-(2x-10)/(x+5)
2、(xy-2x-2y+4)÷(4-2x) 【改个地方】
=(x-2)(y-2)÷[-2(x-2)]
=-(y-2)/2
=(2-y)/2
=1-y/2