Fill in the blanks.
`a xx `__________ `=bxxa`

Answer

To solve the equation \( a \times \_\_\_\_ = b \times a \), we need to identify what can fill in the blank.

### Step-by-Step Solution:

1. **Understand the Equation**: We have \( a \times \_\_\_\_ = b \times a \). This means we need to find a value that, when multiplied by \( a \), gives the same result as \( b \times a \).

2. **Rearranging the Equation**: We can rearrange the equation to isolate the blank. We can divide both sides by \( a \) (assuming \( a \neq 0 \)):
\[ \_\_\_\_ = \frac{b \times a}{a} \]

3. **Simplifying**: Since \( a \) in the numerator and denominator cancels out, we get:
\[ \_\_\_\_ = b \]

4. **Final Answer**: Therefore, the blank can be filled with \( b \):
\[ a \times b = b \times a \]

### Conclusion:
The filled equation is \( a \times b = b \times a \).