Question

qual o valor da adicao algebrica 20-{-10-[-8+(5-12)]-20}?

Answer 1

20 -{-10 -[-8+(-7)]-20}
20 - { -10 -[ -8 -7]-20}
20 -{-10-[-15]-20}
20 -{-10+15-20}
20 -{-30+15}
20 - {-15}
20+15 = 35                          ok