Answer
$-19$
Work Step by Step
The order of operations follow the following hierarchy (PEMDAS rule):
(i) Parentheses/grouping symbols
(ii) Exponents
(iii) Multiplication/Division, whichever comes first from the left
(iv) Addition/Subtraction, whichever comes first from the left
Use the rule above to obtain:
$=-9+2[20 \div (-4)]
\\=-9+2(-5)
\\=-9+(-10)
\\=-19$
