Simplify :
`(-6)-{(-28)div(-7)}`

Answer

To simplify the expression `(-6) - {(-28) div (-7)}`, we will follow these steps:

### Step 1: Simplify the expression inside the curly brackets
The expression inside the curly brackets is `(-28) div (-7)`.

**Calculation:**
- When dividing two negative numbers, the result is positive.
- So, `(-28) div (-7) = 28 div 7 = 4`.

### Step 2: Substitute the result back into the expression
Now that we have simplified the curly bracket, we can substitute it back into the expression.

**New Expression:**
- The expression now becomes `(-6) - 4`.

### Step 3: Perform the subtraction
Now we need to perform the subtraction of `-6` and `4`.

**Calculation:**
- When subtracting a positive number from a negative number, we can think of it as adding the absolute values and keeping the negative sign.
- So, `-6 - 4 = - (6 + 4) = -10`.

### Final Answer:
The simplified expression is `-10`.

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