Final answer:
The term that completes the product as the difference of squares is 9.
Step-by-step explanation:
The term that completes the product as the difference of squares is 9.
When we have an expression in the form a2 - b2, it can be factored into (a + b)(a - b).
In this case, we have -5x - 3x - 5x, which can be written as (-5x)(-1) + (-3x)(1) - 5x.
Factoring it further, we get ((-5x + 3x)(-1 + 1) - 5x), which simplifies to (-2x)(0) - 5x.
The product is then -2x - 5x = -7x.
Therefore, the correct answer is 9.