Question

Calcule o valor das expressões:
a) -77 - (7-18)+[70-(49-81)]=

b) -(-2)-7-[-18+4+(7-15)]=

c)- {20-(2-10)+[-30-(-70)]}=

Answer 1

a) -77-11+[70+32]=
    =-77-11+102=
    =-77-91=
    = -168
b)2-7-[-18+4+8]=
   =5-[-14+8]=
   =5-[-6]=
   =5+6=
   =11
c)-{20+8+[-30+70]}=
  =-{20+8-40}=
  =-{28-40}=
  =12

Answer 2

A) -76-(7-18)+[70-(49-81)]

-76-(-11)+[70-(-32)]

-76+11+[70+32]

-76+11+[102]

-76+11-102

-15