What is the equivalent expression for writing "5.7" in words?

The expression "5.7" can be accurately described in words as "five and seven tenths." This is because the number "5" represents the whole number part, while the ".7" indicates seven tenths, which means that it is a fraction of ten.

In numerical terms, the "5" signifies five complete units, and ".7" is equivalent to the fraction 7/10. Therefore, when combining these two components, the most precise way to articulate "5.7" is "five and seven tenths," effectively capturing both the whole number and the decimal part in a clear format.

The other choices do not convey the complete and correct representation of the number. "Five and seven" neglects to mention the decimal context, while "Five point seven" is a direct but less formal way of articulating the numeral, and "Five plus seven tenths" introduces an additive operation that isn't inherent to how the number is structured. Thus, "five and seven tenths" is the most accurate verbal depiction.