Simplify

-9[-15-(45-12)]=

-9[-15-(45-12)]

= -9[-15 - 45 + 12]
= -9[-48]
= 432

-9[-15-(45-12)]

To simplify the expression -9[-15-(45-12)], we'll follow the order of operations (also known as PEMDAS).

1) Start by simplifying the expression inside the parentheses:
-9[-15-(45-12)]
-9[-15-33]

2) Next, perform the subtraction:
-9[-15-33]
-9[-48]

3) Finally, perform the multiplication:
-9 * (-48)

To simplify the expression -9 * (-48), we multiply the two negative numbers together:

-9 * (-48) = 432

Therefore, the simplified expression is 432.