(1,8а-а)-(1,8а+а-2)

To simplify the expression \((1.8a - a) - (1.8a + a - 2)\), follow these steps:

1. Simplify the first part: \[ 1.8a - a = (1.8 - 1)a = 0.8a \]

2. Simplify the second part: \[ 1.8a + a - 2 = 1.8a + 1a - 2 = (1.8 + 1)a - 2 = 2.8a - 2 \]

3. Now substitute these back into the expression, giving: \[ 0.8a - (2.8a - 2) \]

4. Distribute the negative sign: \[ 0.8a - 2.8a + 2 \]

5. Combine like terms: \[ (0.8 - 2.8)a + 2 = -2a + 2 \]

So, the simplified expression is: \[ -2a + 2 \]