Question

Você pode me ajudar?...... 1- A) (7-9)-(4-3-2)+(-6+1) B) 14-(10+1)-(-3)+6-2 C) 2-[7+3+(-6-1)+9] D) -8-[4+(+3+12-7)-(-8-15)]

Answer 1

1-a) (7-9)-(4-3-2)+(-6+1) =
= (-2)-(-1)+(-5) =
= -2+1-5 =
= -6

b) 14-(10+1)-(-3)+6-2 =
= 14-11+3+6-2 =
= 23-13 =
= 10

c) 2-[7+3+(-6-1)+9] =
= 2-[10+(-7)+9] =
= 2-[19-7] =
= 2-12 =
= -10

d) -8-[4+(3+12-7)-(-8-15)] =
= -8-[4+8-(-23)] =
= -8-[12+23] = 
= -8-35 =
= -43