5x - (6x-(7x-(8-9)))

Question

5x - (6x-(7x-(8-9)))

Answer 1

Я так понимаю упростить
5x-(6x-(7x+1))
5x-(6x-7x-1)
5x-6x+7x+1
6x+1

Answer 2

5x-(6x-(7x-(-1)))
5x-(6x-(7x+1)))
5x-(-x-1)
6x+1