Answer
$-12$
Work Step by Step
RECALL:
The order of operations follow the PEMDAS rule:
First Priority:
P - Parentheses or grouping symbols
Second Priority:
E - Exponents
Third Priority:
M/D - Multiplication or Division, whichever comes first from the left
Fourth Priority:
A/S - Addition or Subtraction, whichever comes first from the left
Use the PEMDAS rule to obtain:
$=2-5\cdot 4-[6 \cdot (-1)]
\\=2-5\cdot 4 - [-6]
\\=2 - 20 - (-6)
\\=-18-(-6)
\\=-18+6
\\=-12$