write an equivalent expression by distributing the "-" sign outside the parentheses

To distribute the negative sign outside the parentheses, you will multiply each term inside the parentheses by -1. Here's how it works:

\[ -(3.7u - 5v + 0.4) = -3.7u + 5v - 0.4 \]

Thus, the equivalent expression is:

\(-3.7u + 5v - 0.4\)