Answer
-32
Work Step by Step
$5(-8)-[6-(2-4)]+(12-16)^2$ $\longrightarrow$resolve expressions in parenthesis/brackets
=$5(-8)-[6-(-2)]+(-4)^2$
=$5(-8)-8+(-4)^2$ $\longrightarrow$ resolve exponents
=$5(-8)-8+16$ $\longrightarrow$multiply
=$-40-8+16$ $\longrightarrow$add/subtract working left to right
=$-48+16$
=$-32$
