Simplify :
`8-{12-(9-overline(7-4))}`

Answer

To simplify the expression \( 8 - \{ 12 - (9 - \overline{(7 - 4)}) \} \), we will follow the order of operations, which involves resolving the innermost brackets first and then moving outward.

### Step-by-Step Solution:

1. **Identify the innermost operation**: Start with the expression inside the overline, which is \( 7 - 4 \).
\[ 7 - 4 = 3 \]
Now, substitute this back into the expression:
\[ 8 - \{ 12 - (9 - 3) \} \]

**Hint**: Always start with the innermost brackets first.

2. **Next, resolve the expression in the parentheses**: Now we simplify \( 9 - 3 \).
\[ 9 - 3 = 6 \]
Substitute this back into the expression:
\[ 8 - \{ 12 - 6 \} \]

**Hint**: After resolving the innermost brackets, move to the next set of brackets.

3. **Now, simplify the expression in the flower brackets**: Next, we calculate \( 12 - 6 \).
\[ 12 - 6 = 6 \]
Substitute this back into the expression:
\[ 8 - 6 \]

**Hint**: Always simplify the brackets from the innermost to the outermost.

4. **Finally, perform the last subtraction**: Now, we calculate \( 8 - 6 \).
\[ 8 - 6 = 2 \]

**Hint**: The last step is to perform the final arithmetic operation.

### Final Answer:
The simplified result is \( 2 \).