当x取何值时,式子1/2[2x-1/3(10-7x)]-x-x/2的值比1/3[x-1/2(x+1)]的值小3?
问题描述:
当x取何值时,式子1/2[2x-1/3(10-7x)]-x-x/2的值比1/3[x-1/2(x+1)]的值小3?
答
{1/2[2x-1/3(10-7x)]-x-x/2}+3=1/3[x-1/2(x+1)]
x-1/6(10-7x)-3x/2=x/3-1/6(x+1)-3
6x-10+7x-9x=2x-x-1-18
x=-3
答
x-1/6(10-7x)-3x/2=x/3-1/6(x+1)-3
6x-10+7x-9x=2x-x-1-18
x=-3