Question

Me Ajuda Em..... 1- A) (-5+9)+[-4+(5-2+6)-9]-(1-7) B) -20+{-5+[(-12+30)+(-4-7)]}

Answer 1

A) 
(-5+9)+[-4+(5-2+6)-9]-(1-7)
(4)+[-4+9-9]-(-6)
(4)+[-4]+(6)
4-4+6 = 6

B)
-20+{-5+[(-12+30)+(-4-7)]}
-20+{-5+[(18)+(-11)]}
-20+{-5+[7]}
-20+{-5+7}
-20+{2}
-20+2 = -18