若｜y+5｜+(5x+1)^2=0,求-3(2x-y)-｛7x-[6x+2y-(10x-8y)]-x-2(3x-4y)｝的值
问题描述：
若｜y+5｜+(5x+1)^2=0,求-3(2x-y)-｛7x-[6x+2y-(10x-8y)]-x-2(3x-4y)｝的值
答
解
∵/y+5/+(5x+1)²=0
∴y+5=0.5x+1=0
∴y=-5,x=-1/5
原式
=-6x+3y-{7x-(10y-4x)-x-2(3x-4y)}
=-6x+3y-[7x-10y+4x-x-6x+8y]
=-6x+3y-(4x-2y)
=-6x+3y+2y-4x
=-10x+5y
=-10×(-1/5)+5×(-5)
=2-25
=-23