Answer
-26
Work Step by Step
We follow order of operations, so we first consider everything inside of the brackets, then we multiply, and then we add/subtract everything else:
$-9-2[4-(-10+6)]-1$
=$-9-2[4-(-4)]-1$
=$-9-2[4+4]-1$
=$-9-2(8)-1$
=$-9-16-1$
=$-25-1$
=$-26$
