计算:7x-{-3x+[-2x-(8x-1)]-4}

问题描述:

计算:7x-{-3x+[-2x-(8x-1)]-4}

20x+3

7x-{-3x+[-2x-(8x-1)]-4}
=7x-[-3x+(-2x-8x+1)-4]
=7x-(-3x-2x-8x+1-4)
=7x-(-13x-3)
=7x+13x+3
=20x+3