Question

(-6+4)-{4-[3-(8+9-2)-7]-35+(4+8-15)}

Answer 1

Saludos

(-6+4) - {4-[3-(8+9-2)-7]-35+(4+8-15)} =
-2 - {4-[3- 15 - 7] - 35 -3} =
-2 - {4 + 19 - 35 -3} =
-2 -{ 23 - 38}
-2 - -15 = 
-2 + 15 =
13