Add : 6- 3a + b , a - 7-6b and 3b + 2- a.

Answer

To solve the problem of adding the algebraic expressions \(6 - 3a + b\), \(a - 7 - 6b\), and \(3b + 2 - a\), we will follow these steps:

### Step 1: Write down the expressions
We start by writing down all the expressions we need to add:
\[ (6 - 3a + b) + (a - 7 - 6b) + (3b + 2 - a) \]

### Step 2: Remove parentheses and combine like terms
Next, we will combine all the terms together:
\[ 6 - 3a + b + a - 7 - 6b + 3b + 2 - a \]

### Step 3: Group the like terms
Now, we will group the like terms: the terms with \(a\), the terms with \(b\), and the constant terms.
- Terms with \(a\): \(-3a + a - a\)
- Terms with \(b\): \(b - 6b + 3b\)
- Constant terms: \(6 - 7 + 2\)

### Step 4: Simplify each group
Now we simplify each group:
- For \(a\):
\[ -3a + a - a = -3a + 1a - 1a = -3a \]
- For \(b\):
\[ b - 6b + 3b = 1b - 6b + 3b = -2b \]
- For constants:
\[ 6 - 7 + 2 = -1 + 2 = 1 \]

### Step 5: Combine the simplified terms
Now we combine all the simplified terms:
\[ -3a - 2b + 1 \]

### Final Answer
Thus, the final answer is:
\[ -3a - 2b + 1 \]

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